4 - Reactivity

Question 1

What is Oxidisation?

Answer 1

Loss of Electrons (makes a + ion)
or the reaction with/gain of oxygen

Question 2

What is Reduction?

Answer 2

Gain of Electrons (makes a - ion)
or the removal of oxygen

Question 3

What are the 3 most reactive metals?

Answer 3

Potassium
Sodium
Calcium

Question 4

What are the 3 least reactive metals?

Answer 4

Copper
Silver
Gold

Question 5

What makes a metal more reactive?

Answer 5

How easily they loose their electrons and form a positive ion

Question 6

Which metals won’t react with dilute acids? Why?

Answer 6

The ones below Hydrogen (Cu, Ag, Gold)
as they’re less reactive with hydrogen

Question 7

What experiment can you do to determine how reactive a metal is?

Answer 7

Place a little piece of metal into dilute hydrochloric acid
- More reactive metals (eg Mg, Al) will vigorously fizz
- Less reactive metals (eg Zn, Fe) will bubble a bit
- Unreactive metals (Cu, Ag) won’t do anything

Question 8

What is the equation for reacting a metal with water?

Answer 8

metal + water –> metal hydroxide + hydrogen

Question 9

How can water be used to test a metal’s reactivity?

Answer 9

Similar to dilute acids - if hydrogen gas bubbles appear you can tell the reactivity from them
- Very reactive metals (K, Na, Li, Ca) will react vigorously lots of bubbles
- Less reactive metals won’t react

Question 10

In terms of water, what do less reactive metals react with?

Answer 10

Less reactive metals (Mg, Zn, Fe) won’t react with cold water but will react to steam
Copper won’t react to water or steam, too unreactive

Question 11

What is the equation for reacting a metal with steam?

Answer 11

(less reactive) metal + steam –> metal oxide + hydrogen