Why Does Reactivity Decrease Down Group 7?

Why does reactivity decrease down group 7 but increase down group 1?

Group 7 – GCSE Chemistry (Combined Science) AQA Revision – Study Rocket

• What you need to know:
• The properties of group 7 elements.
• Group 7 elements are known as the halogens,
• Properties of the halogens:
• They are diatomic (travel in pairs, i.e Br2)
• They are coloured vapours at room temperature:

1. Fluorine is a poisonous yellow gas
2. Chlorine is a poisonous green gas
3. Bromine is a poisonous brown liquid or orange gas.
4. Iodine is a poisonous grey solid or a purple gas.

1. What you need to know:
2. How group 7 elements react with metals and nonmetals.
3. How melting and boiling points increase down group 7 and why.
4. How relative atomic mass increase down group 7 and why.

Reactivity decreases down the group, This is because group 7 elements react by gaining an electron, As you move down the group, the amount of electron shielding increases, meaning that the electron is less attracted to the nucleus. For this reason, fluorine is the most reactive halogen and astatine is the least reactive of the halogens.

• Melting and boiling points: Melting/boiling points increase down the group,
• This is because the atomic radii increase down the group, increasing the amount of intermolecular forces holding each molecule together.
• Relative atomic mass: Relative atomic mass increases down the group,
• This is because group 7 elements react by gaining an electron,

As you move down the group, the amount of electron shielding increases, meaning that the electron is less attracted to the nucleus. Reactions with non-metals: Halogens form covalent bonds with other non-metal atoms when they react. This is a sharing of electrons.

Why does the reactivity of halogens decrease?

The reactivities of the halogens(17th group) decrease down the group ( At atomic radius increases in size with an increase of electronic energy levels. This lessens the attraction for valence electrons of other atoms, decreasing reactivity.

Does group 7 reactivity decrease down the group?

Explaining reactivity – As we descend Group 7, the reactivity decreases. For stability, the atom needs to have a full outer shell. Group 7 elements need to gain 1 electron to have a full shell. As a result, a negative ion is formed: Cl + e – → Cl – As we descend the group:

• there are more shells between the nucleus and the outer electron
• the force of attraction between the nucleus and outer electron decreases
• it becomes harder to gain the outer electron

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Why is group 7 more reactive up the group?

Why do halogens get more reactive going upwards in group 7? – Halogens from bromide to fluorine get more reactive because the force of attraction between the nucleus (core) and the outer electron get stronger as you go up group 7 elements.

1. The distance “a” is less than “c” and the force of attraction between the nucleus and the outer shell increases with shorter distances.
2. The fewer electron shells (rings) between the nucleus and the outer shell (ring) also has less shielding effect and again this increases the electron attraction.
3. The outer shell will more easily attract another electron, which needs an electron to complete its full outer shell, when there is more attractive force.
4. A useful mnemonic picture to help you recall that:
5. As you go down group 1 (the alkali metals) in the periodic table, the elements get more reactive.
6. As you go up group 7 (the halogens), again the elements get more reactive.
7. Is as follows:

To remember how the reactivity of the alkali metals and halogens increases or decreases, put a pin in the middle of the periodic table and spin it anti-clockwise. Drunks fall down, angels rise.

Why is the reactivity of group 1 and 7 different?

Elements react by gaining or losing electrons. Elements wants to reach the stable state of having 8 electrons in the outermost ring, so group 1 elements react by losing an electron, since they have only 1 electron in their outermost shell. Group 7 elements however have 7 electrons in their outermost shells, so they react by gaining an electron to form an outermost ring of 8 electrons.

1. Group 1 elements get more reactive down the group becasue with each step down the group the number of full electron rings increases by 1 and the outermost electron is further away from the positive nucleus.
2. The further away the outermost negative electron is from the positive nucleus, the weaker the force of electrostatic attraction between the two is and the easier it is for the element to react as less energy is required to remove the electron.

Group 7 elements are less reactive down the group because the electron shells have a repulsive effect on the reacting electron, which weakens the force of electrostatic attraction between it and the positive nucleus.

Why does reactivity go down the group?

An atom is made in such a way that the nucleus with the positive charges (protons) is in the centre and the negative charge (electrons) are arranged in shells around it. All group 1 metals have one electron in its outer shell. As we go down the group, the atom gets bigger.

What determines the reactivity of halogens?

Oxidising Ability of Halogens –

The reactions of halogens involve the halogen gaining an electron to achieve a full outer shell. Halogens are found in Group 7 of the periodic table meaning that they have 7 electrons in their outermost shell. This means that when they react, they gain one electron to achieve a full outer shell like noble gases. The reactivity of halogens decreases as you move down Group 7. Halogens become less reactive as you move down the group as the atomic radius of the element increases which means that the distance between the outer shell of electrons and the nucleus increases. There is a reduced attraction between the nucleus and the outermost shell so it is more difficult to gain an extra electron. This is why the reactivity decreases down the group.

The Halogens – Reactions with Halogens

As the halogens become less reactive down the group, their oxidising ability decreases. Remember that oxidation is a gain of electrons. Halogens become less oxidising as you move down the group as it is more difficult to gain an electron. Displacement reactions are a good test for oxidising ability. The oxidising strength of the halogens can be compared by carrying out displacement reactions involving the halide ions. It is worth to note here that a halide in solution will only be displaced by a halogen that is above it in the periodic table.

The Halogens – Reactions with Halogens

Displacement reactions can also be used to identify the halogen present in the solution. To identify the halogen present in the solution you look out for the colour change and compare it to the table below

The Halogens – Reactions with Halogens

What does the reactivity of halogens depend on?

Hint: Reactivity of the halogens depends on their electronegativity.

Why does reactivity increase and decrease?

Trends in Reactivity of Elements – Generally, all chemical and physical properties manifest the electronic configuration of elements. As the electronic configuration differs from element to element, the relation between fundamental properties like ionic and atomic radii, ionisation enthalpy, electron affinity, and electronegativity also differs.

Atomic and Ionic Radius:

On going along the group, ionic and atomic radii of atoms increase. As a result, reactivity increases. The number of electrons in the outer shell remains the same while moving down the group. But there is a gradual increase in the number of shells of the same group of atoms.

Hence, there will be less electron shielding on the valence electron, and it can show high reactivity. While moving along a period, atomic or ionic radii decrease. The electrons enter the same valence shells, increasing their attraction toward the nucleus. Hence, the outermost shells pull near the nucleus, and there is a decrease in the radii of atoms.

There is also an increase in electron density which makes the atom more reactive. Hence, reactivity increases from moving across a period.

Ionisation Energy:

Ionisation energy is the amount of energy that is required to pull the electrons from the outermost shell. When you go through top to bottom, i.e., along with a group, the distance between the nucleus and valence shell increases, and attraction between both decreases.

Electron Affinity:

Electron Affinity is the amount of change in energy when an electron in a gaseous state is applied to a neutral atom to form an anion. On moving down the group, there is a decrease in the electron affinity of elements. It is because, as the size of an atom increases, the valence electrons get further away from its nucleus.

Electronegativity:

The potential of an atom to attract a shared pair of electrons towards itself is called electronegativity. While moving down the group, the electronegativity of atoms decreases. It is because the number of valence shells is increasing, and the attraction between valence electrons and the nucleus decreases.

Why do halogens get darker down the group?

As the ionization energy decreases, the electron tends to easily excite to the higher energy level and the increase in atomic radii leads to absorb more visible light. Thus, the Halogens get darker down the group.

Why does boiling point decrease down group 7?

Physical properties of the halogens –

How does the mass and boiling point change down Group 7? As you go down group 7, the r elative atomic mass increases and the boiling point of halogens also increases. So fluorine has the lowest atomic mass and the lowest boiling point whereas astatine has the highest atomic mass and the highest boiling point. The boiling point is affected by the intermolecular forces. Between atoms of a particular element, there are weak attractive forces known as intermolecular forces, When molecules are boiled or melted, these intermolecular forces are overcome. Down group 7, the melting and boiling points increase, The atoms increase in size, as they gain extra electron shells, and the intermolecular forces become stronger, More energy is required to break these forces, thus there are higher melting and boiling points as you go down the group. Halogens have covalent bonding. The halogens are naturally found as simple molecules – a pair of halogen atoms sharing a pair of electrons, this is known as covalent bonding,

GCSE Chemistry – Group 7 Below is a table that summarises the states of the halogens and their colours. GCSE Chemistry – Group 7

Does reactivity increase down every group?

Explaining the trend in reactivity – As you go down the group the reactivity of the Group 1 increases because:

The atoms become larger, This is due to the number of shells increasing. Therefore, the outer electron is further away from the positive nucleus, as you go down the group. The electrostatic attraction of the outer electron to the positive nucleus decreases as you go down group 1. The number of electron shells increases, This increases the shielding effect the positively charged nucleus has on the outer electron. Therefore, the attraction of the outer electron to the nucleus decreases as you go down group 1.

Therefore, as you go down the group the outermost electron becomes easier to lose and the reactivity increases as you go down the group. GCSE Chemistry – Group 1: Reactivity The link to download the notes will be sent to your email

Why are group 7 nonmetals halogens the most reactive?

Summary –

• The halogens all have seven electrons in their outer shells.
• The electron configuration in the outer shell is \(ns^2np^5\).
• As the atomic number increases, the reactivity of the halogens decreases.
• Fluorine and chlorine exist as gases at room temperature, while bromine is a liquid, and iodine is a solid.

Is group 7 on the periodic table highly reactive?

Group 7A (or VIIA ) of the periodic table are the halogens : fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). The name “halogen” means “salt former”, derived from the Greek words halo- (“salt”) and -gen (“formation”). The Group 7A elements have seven valence electrons in their highest-energy orbitals ( ns 2 np 5 ).

1. This is one electron away from having a full octet of eight electrons, so these elements tend to form anions having -1 charges, known as halides : fluoride, F – ; chloride, Cl -, bromide, Br -, and iodide, I -,
2. In combination with other nonmetals, the halogens form compounds through covalent bonding.

In their elemental form, the halogens form diatomic molecules, X 2, connected by single bonds. Since all of the halogens have one unpaired electron in their atomic forms, it is easy for them to “pair up” to form diatomic molecules. The X 2 molecules are nonpolar, so the only interactions between them are fairly weak London forces, but as the size of the atoms increase, the London forces become stronger, increasing their melting and boiling points: fluorine is a gas which liquefies at -188 C, chlorine is a gas which liquefies at a much higher temperature of -34 C; bromine is a liquid which boils at 59 C; and iodine is a solid which melts at 113 C and boils at 184 C.

1. The halogens are extremely reactive (especially fluorine), and are not found naturally in their elemental forms.
2. They are usually found in combination with various metals in minerals, or in combination with other nonmetals in molecular compounds.
3. The halogens also form compounds with carbon easily; organic molecules containing carbon are often known as alkyl halides, or organohalides, and have many different household and industrial uses.

In combination with hydrogen (which also has one unpaired electron), the halogens form the hydrohalic acids : hydrofluoric acid (HF), hydrochloric acid (HCl), hydrobromic acid (HBr), and hydroiodic acid (HI). Fluorine (F, Z=9). In its elemental form, fluorine (F 2 ) is a pale yellow gas; it is extremely reactive and toxic.

• In fact, a large number of chemists who tried to isolate elemental fluorine — which turned out to be an extremely difficult task — died at relatively early ages.
• See Isaac Asimov’s book, Asimov on Chemistry (1974), “Death in the Laboratory” for more.) The name of the element is derived from Latin word fluere, which means “to flow.” It is found in the Earth’s crust at a concentration of 950 ppm, making it the 13th most abundant element; it is also found in seawater at a concentration of 1.3 ppm.

It is found in the ores fluorite, cryolite, and fluorapatite, In its ionic form, fluoride (F – ), it essential in the diet, but only in small doses. It strengthens bones and teeth by becoming incorporated into the hydroxyapatite crystals, 3 Ca(OH) 2, of bone and enamel, converting some of it to the even harder (and more acid-resistant) form of fluorapatite, 3 CaF 2,

Fluoride is used in toothpaste, and is often added to municipal drinking water, at concentrations at or below 1 ppm, to protect against tooth decay. (At least in small doses, it has no effect on anyone’s ” precious bodily fluids,”) Fluorine atoms form very strong bonds to carbon atoms, so fluorine is incorporated into many organic molecules, including the chlorofluorocarbons, which contain carbon, chlorine, and fluorine, which were widely used as propellants and refrigerants until their ozone-destroying properties were discovered (see entry on Freon-12 in the Alkanes section of the Molecule Gallery ), and also in Teflon (see entry on Teflon in the Polymers section of the Molecule Gallery ).

Fluorine is also found in hydrogen fluoride, or hydrofluoric acid, HF, a weak acid. (When dealing with acids and bases, “weak” means that only a small percentage of the acid form dissociates into “H + ” and “F – ” ions.) It is used in etching glass, cleaning stainless steel, and in processing uranium ore.

(In the processing of uranium, uranium in the ore is transformed into uranium hexafluoride, UF 6, which can be sublimed into the gas phase; in this form, fissionable uranium-235 isotopes can be separated from non-fissionable uranium-238 isotopes by gas diffusion.) Hydrofluoric acid is toxic and corrosive, and eats through glass (it must be stored in plastic bottles); it penetrates the skin quickly, and causes intense pain.

Concentrated solution can also start reactions with calcium ions in the body, causing hypocalcemia (an electrolyte disturbance resulting from loss of calcium), cardiac arrest, or death. Chlorine (Cl, Z=17). Chlorine in its elemental form (Cl 2 ) is a yellow-green gas; it is poisonous (it was the first toxic gas to be used in gas warfare during World War I), and too reactive to be found in nature in the elemental form.

• The name of the element is derived from the Latin word for greenish-yellow, chloros,
• It is found in the Earth’s crust at a concentration of 130 ppm, making it the 20th most abundant element; in seawater, its concentration is about 1.8%.
• It is found in the form of chloride anions, Cl -, in the minerals halite and sylvite, chlorargyrite, and in seawater.

Industrially, chlorine is produced from the electrolysis of sodium chloride. Chlorine is used to disinfect drinking water and wastewater, in bleaches, and in the manufacture of chlorinated organic compounds (such as the vinyl chloride used in making the plastic PVC, polyvinyl chloride).

• Chlorine is also found in hydrogen chloride, a colorless gas with a sharp, irritating smell.
• Aqueous solutions of hydrogen chloride are known as hydrochloric acid; concentrated hydrochloric acid is about 37% HCl (about 12 moles/L).
• Hydrochloric acid is also known as “muriatic acid,” and under this name is often sold with swimming-pool supplies.

It is used in the synthesis of organochlorine compounds, the “pickling” of steel and other metals to dissolve scale from their surfaces, and many other uses. Hydrochloric acid is also produced in the stomach, where it serves to break down complex foods.

Chlorine is found in bleaches and cleaners, usually in the form of sodium hypochlorite, NaOCl, which is also used to kill bacteria in drinking water. Carbon tetrachloride, CCl 4, used to be used in dry cleaning and as a spot remover; this substance is now restricted by the Montreal Protocols ( link ) because of its effect on the ozone layer.

Chloroform, or trihalomethane, is a very commonly used organic solvent; chloroform vapor is a anesthetic: James Young Simpson was the first to use chloroform as an anesthetic during childbirth in 1846 (presumably, not on himself!), and it was widely used in surgery in the 19th and early 20th centuries.

However, since chloroform is carcinogenic, and toxic to the liver, it is not widely used for this purpose anymore. (It’s also useful for knocking out giant apes,) Bromine (Br, Z=35). Bromine is a dark, reddish-brown liquid at room temperature (the only nonmetallic element that is a liquid at room temperature) with a terrible smell.

The name “bromine” is derived from the Greek word for “stench,” bromos, It is found in the Earth’s crust at a concentration of 0.4 ppm, making it the 62nd most abundant element; it is also found in seawater at a concentration of 65 ppm. It is found as bromide ions, Br -, in the ore bromargyrite, in seawater, and some natural sea-salt deposits and brines.

• Bromine is often incorporated into organic compounds; organobromo compounds are very useful in many organic synthesis reactions.
• Bromine is also found in compounds called halons, which contain carbon atoms to which fluorine, fluorine, and sometimes chlorine, are also attached.
• These compounds are used in fire extinguishers, since they do not damage electronic equipment.

Methyl bromide, CH 3 Br, used to be used as a soil fumigant to kill insects and bacteria, but its use is being phased out under the Montreal Protocols. Iodine (I, Z=53). Iodine forms dark, shiny, purple crystals at room temperature. The name come from the Greek word iodes, meaning “violet.” It is found in the Earth’s crust at a concentration of 0.14 ppm, making it the 64th most abundant element; it is also found in seawater at a concentration of 0.06 ppm.

It is found in the ores iodargyrite and lautarite, in seawater, and some natural sea-salt deposits and brines. Iodine is toxic, but it is so much less reactive than the other halogens that it is not as dangerous, and in low concentrations it can be used as an antibacterial agent. “Tincture of iodine” is a solution of 3% elemental iodine in a mixture of ethanol and water, commonly used as a disinfectant for cleaning wounds and sanitizing water.

Iodine (in the form of the iodide anion, I – ) is essential in the diet; it accumulates in the thyroid gland, where it is incorporated into hormones that help to regulate metabolic functions. Iodine deficiency results in a condition called goiter, in which the thyroid gland becomes enlarged.

Iodine is commonly added to salt (iodized salt) in the form of potassium iodide (KI), sodium iodide (NaI), and potassium iodate (KIO 3 ). Radioactive iodine-131, a beta emitter which decays to xenon-131 with a half-life of 8 days, is used to diagnose thyroid problems. Silver iodide, AgI, is light-sensitive, and is used in photography; it is also used in seeding clouds to promote the formation of rain.

Astatine (At, Z=85). Astatine is a radioactive element. The name of the element is derived from from the Greek word astatos, which means “unstable.” It is found in the Earth’s crust in only trace amounts, and is one of the ten least abundant compounds.

Is it true the further down group 7 you go the more reactive the elements get?

As you move down group 7 from fluorine to iodine, the reactivity of the elements decreases. The halogens are non-metals and when non-metals react with metals, they GAIN the electrons that the metals lose. As you move down group 7, the atomic radius get bigger (more protons, more electrons, more shells) and so the negatively charged electrons in the outer shell move further away from the positively charged nucleus.

What is the order of reactivity of group 7?

The order of reactivity is: chlorine > bromine > iodine.

What does group 7 react with?

Aims of this page – After studying this page, you should be able to:

recall physical properties of chlorine, bromine and iodinedescribe trends in physical properties of these elementspredict the properties of other group 7 elementsexplain the trend in reactivity in group 7describe and explain displacement reactions between group 7 elements.

The group 7 elements are placed on the right of the periodic table. They are called the halogens because they react with metals to form salts (from Greek hal – meaning ‘salt’ and – gen meaning ‘to produce’). You need to know details about chlorine, bromine and iodine. These are all reactive non-metals that exist as diatomic molecules. The table summarises some of their physical properties.

Halogen	Colour	State at room temperature	Chemical formula	Relative formula mass, M r
Chlorine	Pale yellow	Gas	Cl 2	71
Bromine	Red-brown	Liquid	Br 2	160
Iodine	Grey-black	Solid	I 2	254

The other halogens are fluorine (placed at the top of group 7), and astatine and tennessine (placed below iodine in group 7). Bromine is a corrosive, toxic liquid that is harmful to the environment Fluorine is the most reactive non-metal element. It was first isolated by Henri Moisson in 1886. He received the Nobel Prize in Chemistry in 1906 for his work.

Why do halogens and alkali react aggressively?

Purpose: After watching a video that introduces them to the periodic table, students will answer questions that prompt them to identify general patterns in the table. A second set of videos focused on reactivity will encourage students to use their observations to identify trends and predict behavior in reactivity among metals and nonmetals.

Approximate time: 50 minutes Supplies: Activity Guide for Students Handouts showing the periodic table or a large periodic table wall chart Classroom computer projector to show video clips demonstrating chemical reactivity Directions for teachers: In the first part of this activity, students will get to know the periodic table through “The Periodic Table Song,” various versions of which are available on YouTube.

A new version of the song is at Periodic Table Song, Plan to play the song at least twice to get your students thinking about the table and its general set up. Allow students to listen generally once, then ask students to listen again and answer the questions provided.

1. After the lesson, you could also share a classic version of the song by Tom Lehrer,
2. After students have completed the first set of questions, they will observe and predict trends in reactivity of metals and nonmetals based on the suggested videos below.
3. Have students create a data table to write down the physical properties of each metal element they will see in the video: lithium (Li), sodium (Na), potassium (K), magnesium (Mg), calcium (Ca) and strontium (Sr).

Students should include space to make observations of each metal’s reaction with water. Have students create a second data table to write down the physical properties of each nonmetal in the videos: chlorine (Cl), bromine (Br), iodine (I) and oxygen (O).

Students should include space to make observations of each nonmetal’s reaction with aluminum. Play the following suggested videos or similar video clips and ask students to answer the questions that follow. Suggested videos: Alkali metals reacting with water Chemistry of the group w elements (reactions with water) Reactivity of halogens Other optional videos: Reaction (explosion) of alkali metals with water Mythbusters: Alkali metal explosion If you have the resources and equipment to safely do so, you could demo some of these reactions in the classroom.

But even without a live demo, students should be able to make observations about the physical properties of the elements and observe trends in reactivity. Directions for students: After listening to “The Periodic Table Song,” answer the questions that follow.1.

What is the pattern you observe for the order in which the elements are presented during the song? List the first 12 elements mentioned in the song. The periodic table is being read like a book: Elements are listed starting from the top, far left element (hydrogen) across the whole row before going down to the next row far left.

The first 12 elements are: H, He, Li, Be, B, C, N, O, F, Ne, Na and Mg.2. The atomic number defines the type of atom, or element, that exists. How does the number of protons, or the atomic number, differ from one element to the next in the song? Each element mentioned has one more proton than the previous element mentioned.3.

What is the refrain of the song? “This is the periodic table, noble gases stable, halogens and alkali react aggressively. Each period we’ll see new outer shells, while electrons are added moving to the right.” 4. What does the refrain tell you about the reactivity of noble gases? Where are noble gases located on the periodic table? The rightmost column (noble gases) contains elements that have a stable configuration of electrons for each energy level, or row on the periodic table.

Nobel gases do not generally give or accept any electrons, so they are nearly chemically inert.5. Where are alkalies (metals) and halogens (nonmetals) located on the periodic table? Why do you think elements like the halogens and alkalies would react? Alkali metals are in the leftmost column on the periodic table and halogens are to the left of the noble gases.

Atoms in these columns react to become stable (have a lower energy state). Both the alkalies and the halogens react to become more like noble gases in terms of their number and configuration of electrons.6. Given the long list of elements from the song, where do alkalies (metals) and halogens (nonmetals) always fall in relation to the closest noble gas in the list? How does the proximity to a noble gas affect how aggressively elements react? Halogens are always the element before a noble gas and alkalies are always right after a noble gas.

The closer the elements are to stability, the more aggressively they tend to react.7. What does the refrain tell you will happen to the physical structure of the atoms as you go down a column, hopping from one period, or row, to the next? In your own words, what visual does the video use to show this trend? The refrain says, “each period we’ll see new outer shells.” As you move down a column of the table, generally the element in the row below will have one more completely filled “shell” (energy level) of electrons than the one in the row above.

The video shows a Bohr model of the atom, with a nucleus denoted by a red dot and shows electron shells being added as concentric circles, getting farther away from the nucleus.8. What does the refrain tell you will happen to atoms as you go across a row, “moving to the right?” In your own words, what does the video use to show this trend? The refrain says, “electrons are added moving to the right.” As you move to the right across a row, generally the element to the right will have one more electron in the outermost electron shell (energy level) than the previous element.

The video shows a Bohr model with a nucleus denoted by a red dot and shows electrons being added to existing concentric circles around the nucleus. Directions for students continued: Before watching the videos on reactivity, create a data table to write down the physical properties of each metal element you will see in the video: lithium (Li), sodium (Na), potassium (K), magnesium (Mg), calcium (Ca) and strontium (Sr).

1. Include space to make observations of each metal’s reaction with water.
2. Create a second data table to write down the physical properties of each nonmetal in the videos: chlorine (Cl), bromine (Br), iodine (I) and oxygen (O).
3. Also, include space to make observations of each nonmetal’s reaction with aluminum.

As you watch the videos, fill in your observation table based on what you observe. Then answer the questions that follow.1. Based on your observations, list the metals in each of the following sets from least reactive to most reactive: K, Na, Li Li, Na, K Sr, Ca, Mg Mg, Ca, Sr Na, Mg Mg, Na K, Ca Ca, K 2.

1. Based on your observations, list the following nonmetals from least reactive to most reactive: Cl, Br, I I, Br, Cl 3.
2. Based on your observations and analysis, explain the general reactivity trend of metals as you go across a row from left to right on the periodic table.
3. What about the trend as you go down a column on the periodic table? Metals tend to get less reactive as you move across a period to the right and more reactive as you move down a column.4.

Based on your observations and analysis, explain the general reactivity trend of nonmetals as you go down a column on the periodic table? Based on the reactivity trends of the halogens, nonmetals tend to be less reactive as you move down a column on the table.5.

• In your experience with items made out of aluminum (aluminum cans, foil, etc.), how reactive is oxygen with aluminum? How do you think the reactivity of oxygen with aluminum would compare with the reactivity of fluorine with aluminum? Aluminum reacts with oxygen over time, but it is a slow process.
• For example, an old aluminum can that has been sitting outside for a while can appear to have a rust-like layer on it.

Based on the trend in nonmetal reactivity (the reactivity increases up a column), I would expect fluorine to be much more reactive with aluminum than oxygen would be with aluminum.6. What do you predict is the general reactivity trend of nonmetals as you go across a row from left to right on the periodic table? The reactivity of nonmetals would likely increase as you move across a period to the right.7.

1. What do you notice about the reactivity trends of metals compared with the reactivity trends of nonmetals? The reactivity trends of metals are the opposite of the reactivity trends of nonmetals.8.
2. Atoms react to become more stable either losing or gaining (taking or sharing) electrons.
3. Based on the proximity to a noble gas, do you think metals react by gaining or losing electrons? What about nonmetals? Metals tend to lose electrons and nonmetals tend to gain electrons to become more stable (have an electron structure similar to a noble gas).9.

What patterns of reactivity would you expect from an element like silicon (Si)? Explain. Silicon is the same number of elements away from the noble gas preceding it, Neon (Ne), as it is from the noble gas following it, Argon (Ar). It can probably gain or lose electrons to become stable, because it needs to gain or lose the same number of electrons to have a stable number (configuration) of electrons.

Does reactivity decrease going down?

The farther to the left and down the periodic chart you go, the easier it is for electrons to be given or taken away, resulting in higher reactivity. Period – reactivity increases as you go from the left to the right across a period. Group – reactivity decreases as you go down the group.

Which group decreases in reactivity?

Reactivity will decrease as you travel down group 7 in the periodic table. Group 7 elements need to gain an electron to become stable as they need 8 electrons in their outer shell.

Why do Group 7 elements react in similar ways?

Groups in the periodic table – AQA – Elements in the same group of the periodic table show trends in physical properties, such as boiling point. They have the same number of electrons in their outer shell, so similar chemical properties.

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Atoms of group 7 elements all have seven electrons in their outer shell. This means that the halogens all have similar chemical reactions, When a group 7 element takes part in a reaction, its atoms each gain one electron. These atoms form negatively charged ions, The ions have a stable arrangement of electrons, with a complete outer shell.

Why do group 1 elements increase in reactivity as you go down?

Explaining trends – In a reaction, an atom of a Group 1 element will form an ion with a single positive charge. For example, for sodium forming a sodium ion: Na → Na + + e – A change like this, where an electron is lost, is an example of oxidation, The ions formed have a stable electronic structure, like a noble gas from Group 0. The reactivity of Group 1 elements increases as you go down the group because:

• the atoms get larger
• the outer electron gets further from the nucleus
• the attraction between the nucleus and outer electron gets weaker – so the electron is more easily lost

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Is group 1 more reactive than group 7?

The non-metal elements in Group 7 – known as the halogens – get less reactive as you go down the group. This is the opposite trend to that seen in the alkali metals in Group 1 of the periodic table.

Why do group 1 elements get less reactive as you go down?

Explaining the trend in reactivity – As you go down the group the reactivity of the Group 1 increases because:

The atoms become larger, This is due to the number of shells increasing. Therefore, the outer electron is further away from the positive nucleus, as you go down the group. The electrostatic attraction of the outer electron to the positive nucleus decreases as you go down group 1. The number of electron shells increases, This increases the shielding effect the positively charged nucleus has on the outer electron. Therefore, the attraction of the outer electron to the nucleus decreases as you go down group 1.

Therefore, as you go down the group the outermost electron becomes easier to lose and the reactivity increases as you go down the group. GCSE Chemistry – Group 1: Reactivity The link to download the notes will be sent to your email