Topic 2: Groups 1&7

Question 1

What happens to the reactivity in group 1?

Answer 1

-The reactivity increases going down the group.

Question 2

Observations of group 1 metals?

Answer 2

• Easier to cut going down the group.
• Turns universal indicator blue.
• The float so less dense then water.
• When cut they are shiny inside.
• All react with air.
• The sample of metal gets smaller.

Question 3

Which gas you group 1 metal create when they react with water?

Answer 3

-Hydrogen.

Question 4

Observations of sodium?

Answer 4

• Sodium more reactive then lithium.
• Turned into a ball-melted.
• Softer then lithium.

Question 5

Observations of potassium?

Answer 5

• Lilac flame.
• Turned into a ball.
• Softest metal.
• More reactive then sodium.

Question 6

What is the shielding effect?

Answer 6

-Electrons closer to the nucleus are more strongly attracted then those further away.

Question 7

In group 1 why are the elements more reactive as you go down the group?

Answer 7

-In group 1 bigger atoms (more electrons) are more reactive.

Question 8

What is a anion?

Answer 8

-A negatively charged ion (usual non-metal) one that gained electrons.

Question 9

What is a cation?

Answer 9

-A positively charged ion (usually metal) one that has lost electrons.

Question 10

Define Dissociation?

Answer 10

-The ability for ions to separate from each other, usually in solution.

Question 11

Define Poler molecules?

Answer 11

-Molecules that have very strong inter-molecular forces of attraction, e.g. In water (if water is not poler).

Question 12

Sulphuric acid?

Answer 12

-H2So4(l).

Question 13

Sodium sulphate?

Answer 13

-Na2So4(aq)(aqueous in solution).

Question 14

Sodium chloride?

Answer 14

-NaCl(s).

Question 15

Hydrogen chloride?

Answer 15

-HCl(g).

Question 16

What color do group 1 metals turn universal indicator paper, when mixed with water?

Answer 16

-Blue because it is forming a hydroxide OH-.

Question 17

What is the shielding effect?

Answer 17

• Electrons closer to the nucleus are more strongly attracted then those further away.
• Inner electrons “shield” outer electrons from forces of attraction and from nucleus.
• In group 1 bigger atoms (more electrons) are more reactive.

Question 18

What will happen when hydrogen chloride is dissolved in water?

Answer 18

• It will tern universal indicator paper red, however will not change it if it is dissolved in methyl benzene. use the idea of dissociation to explain this.
• Dissociation= the ability for ions to separate from each other, usually in solution.

Question 19

Define Dissociation?

Answer 19

-The ability for ions to separate from each other, usually in solution.

Question 20

Loss of electrons is called?

Answer 20

-Oxidation.

Question 21

Gain in electrons is called?

Answer 21

-Reduction.

Question 22

• What is oxidizing and what is reducing in this equation =

- 4Fe+3(O2)=2(Fe2)(O2)

Answer 22

• Fe=oxidation.

- O=reduction.

Question 23

The way to remember oxidation and reduction?

Answer 23

-O I L R I G.

Question 24

When a halogen is reduced(gains an electron)?

Answer 24

-It forms a halide.

Question 25

Define Spectator ions?

Answer 25

-Ions that are neither oxidized nor reduced are called spectator ions.

Question 26

What are transitions elements?

Answer 26

-These are (typical metals) They are hard, dense and shiny. they are good conductors of heat and electricity and are also malleable and ductile. They also have high melting points and boiling points, apart from mercury

Question 27

Differences between Group one metals and transitions elements?

Answer 27

- Group 1 metals are soft while the transitions metals are very hard. - Transitions metals are not very reactive, whilst group 1 metals are.

Question 28

What is the difference between hydrogen chloride gas and hydrocloric acid?

Answer 28

-Hydrogen chloride gas has covelent bonds and also dissociates when dissolved in a polar solvent.

Question 29

When are hailides formed?

Answer 29

-Formed when group 7 react with group 1 and visa verse.

Question 30

Properties of group 7?

Answer 30

-Gas, gas, liquid, solid,solid. They are all different colors. They are also highly reactive.

Question 31

How to check if hailade is formed?

Answer 31

-Take one hailide self dissolved in H2O add the other halogen solution. Observe the color changes.

Question 32

Difference between hydrogen chloride gas and acid?

Answer 32

-When hydrogen chloride gas is dissolved in water the solution is hydrochloric acid. Hydrogen chloride is a covalent molecule.But, when it is dissolved in water, it forms H3O+ ion and Cl- ion.

Question 33

When a more reactive halogen is added to a metal halide....

Answer 33

-The reactivity halogen will displace the less reactive halogen to form a new metal halide.

Question 34

Experiments to show the displacement of the halogens?

Answer 34

-Reacting, chlorine and bromine water, iodine solution with potassium chloride, potassium bromide and potassium iodide.

Question 35

Displacement reactions are.....

Answer 35

-Redox reactions.

Question 36

Metals always...

Answer 36

-Metal atoms lose the electron, or electrons, in their highest energy level and become positively charged ions.

Question 37

Non-metals always...

Answer 37

-Non-metal atoms gain an electron, or electrons, from another atom to become negatively charged ions

Question 38

Explain the relative reactivity of the elements in Group 1 in terms of distance between the outer electrons and the nucleus?

Answer 38

-The more the electrons in group one the more reactive the element is.

Question 39

Observations of Florine?

Answer 39

-Pale yellow gas, gas at room temperature.

Question 40

Observations of chlorine?

Answer 40

-Pale green gas, gas at room temperature.

Question 41

Observations of bromine

Answer 41

-Dark red liquid, readily gives off a brown vapor, solid at room temperature.

Question 42

Observations of Iodine?

Answer 42

-Dark (~black) crumbly solid, purple vapor, solid at room temperature.

Question 43

Observations of Astatine?

Answer 43

-Black solid, dark vapor – highly radioactive!, solid at room temperature.

Question 44

-Properties of group 7?

Answer 44

-The boiling point increases gong down the group, colored elements. The group 7 elements react vigorously with group 1 elements such as sodium and potassium. In each case, a metal halide is formed (fluoride, chloride, bromide or iodide).

Question 45

metal + water ->

Answer 45

Metal hydroxide + Hydrogen

Question 46

Test for Hydrogen?

Answer 46

Squeaky pop form burning splint.

Question 47

What happens when Hydrogen Chloride gas is bubbled into water, containing Universal indicator?

Answer 47

- starts Green. - Turns red - becomes acidic H+ ions formed.

Question 48

Differences between the reaction of lithium and potassium reactions?

Answer 48

``` Similarity? Both release hydrogen. Both exothermic Differences? Potassium gives on lilac flame Potassium Melts into a ball. ```

Question 49

Chemical equation between group 1 metal and water?

Answer 49

Metal + water -> metal hydroxide + hydrogen

Question 50

Example of Group 1 reaction? Lithium

Answer 50

lithium + water → lithium hydroxide + hydrogen | 2Li(s) + 2H2O(l) → 2LiOH(aq) + H2(g)

Question 51

Chemical equation for ethanol?

Answer 51

CnH2n + OH | C2H5OH

Question 52

Equation for conversion of ethanol to ethane?

Answer 52

C2H5OH -> C2H4 + H2O

Question 53

State the name for the type of reaction that is done when converting ethanol to ethene?

Answer 53

Dehydration reaction

Question 54

Catalyst used with dehydration reactions?

Answer 54

Aluminium oxide

Question 55

Reactivity in Group 7 as you go down?

Answer 55

The reactivity of group 7 elements decreases down the group.

Question 56

Group 7 why does the reactivity increase as you go down?

Answer 56

- The atoms get larger - The outer shell gets further from the nucleus - The attraction between the nucleus and electrons gets weaker, so an electron is less easily gained.