Topic 3 - reactions of metals with water & acids

Question 1

Reactions with water​ - Group 1 (alkali metals):

Answer 1

React violently with water​

Reactivity increases down the group​

Produce a basic solution​
​
2M(s) + 2H2O(l) → 2M+(aq) + 2OH-(aq) + H2(g)

Question 2

Reactions with water​ - Group 2 (Alkali Earth metals)

Answer 2

Beryllium doesn’t react​

Magnesium will react with steam​

Metals below magnesium will react with water, reaction becomes more vigorous down the group​

Reaction produces hydroxides – basic solutions​
​
M(s) + 2H2O(l) → M(OH)2(aq) + H2(g)​

Question 3

Reactions with water​ - Group 3,4,5,6 + transition metals

Answer 3

Group 3:​
Aluminium appears not to react at all due to the surface oxide layer​
Other group 3 metals are not very reactive with water​
​
Group 4, 5, 6:​
No reaction​
​
Transition metals:​
Slow reaction if any​

Question 4

Reactivity series

Answer 4

List of metals from most to least reactive ​

Reactivity in metals depends on how easily the metal atom loses an electron to have full shells​

The more reactive the metal, the harder it is to extract from it’s ore and the more likely it is found as a compound​
​

Question 5

Patterns of reactivity​

Answer 5

Reactivity of metals decreases across periods because the higher the nuclear charge, the harder it is to lose an electron​

The most reactive metals are in group 1​

Reactivity increases down group 1 as the atoms get bigger​

The order of reactivity is Group 1, Group 2, Group 3, Group 4, Transition metals​

Question 6

Why are there non-metals?​

Answer 6

Carbon is included as some metals can be extracted from ore by displacement with carbon​

Hydrogen is present as metals below hydrogen will not react with dilute acids or water​

Question 7

Reactions with dilute acids​

Answer 7

Metals above copper can react to form metal salts and hydrogen​
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)​
​
More reactive metals will also form salts but the reaction is very violent and therefore dangerous​

Reactions of calcium, strontium and barium with sulphuric acid are more complex as they produce insoluble sulfates which form a protective layer