3.5.3 Metal + Water/Steam reaction

Question 1

What is the metal reactivity series?

Answer 1

Some metals are more reactive than others, the reactivity series shows this:
Highest
K
Na
Li
Ca
Mg
Al
C (non-metal)
Zn
Fe
Pb
H (non-metal)
Cu
Ag
Au
Lowest

Question 2

What do metals react with cold water to make

Answer 2

Metal hydroxide and hydrogen

Question 3

Metal + Water —>

Answer 3

Metal hydroxide + Hydrogen

Question 4

What are two observations from water and metal reaction?

Answer 4

• Effervescence (fizzing)
• Solid disappers

Question 5

Why is there effervescence (fizzing) in a metal and water reaction?

Answer 5

Hydrogen gas is produced.

Question 6

Why does the solid disappear in a metal and water reaction?

Answer 6

The metal is used up in the reaction.

Question 7

What are metals in group 1 called?

Answer 7

Alkali metals

Question 8

What are special properties of Alkali Metals?

Answer 8

• Very reactive
• Soft
• Less dense than H2O
• Low melting points

Question 9

What are observations of the reaction of Lithium and Water?

Answer 9

• Solid floats
• Fizzing
• Solid moves around the surface of water
• Solid disappears

Question 10

What are observations of the reaction of Sodium and Water?

Answer 10

• Solid floats
• Fizzing
• Solid moves around the surface of water
• Solid melts into a sphere
• Solid disappears

Question 11

When universal indicator is added to the reaction between water and metal, what colour does it turn?

Answer 11

Dark blue/purple because metal hydroxides are alkalis because they donate OH-.

Question 12

What are observations of the reaction of Potassium and Water?

Answer 12

• Solid floats
• Fizzing
• Solid moves quickly around the surface of the water
• Sparks and lilac flame
• Solid disappears

Question 13

As you go down the group 1 metals …

Answer 13

… they get more reactive.

Question 14

Explain why when you down the group 1 metals they get more reactive.

Answer 14

When a group 1 metal reacts, it loses its outer-shell electrons to get a full outer shell. This happens more easily down the group because teh atoms get bigger and have more shells. The outer electron is further from the nucleus. The attraction between the nucleus and the outer shell electrons is weaker. Less energy is needed to break the attraction and the metal therefore reacts with smaller amounts of energy and is more reactive.

Question 15

What does the reaction between metal and steam produce?

Answer 15

Metal oxide and hydrogen

Question 16

Metal + Steam —>

Answer 16

Metal oxide + Hydrogen

Question 17

Describe the reaction between metal and steam.

Answer 17

The reaction usually occurs in a horizontal tube.
Some wet wool is heated to generate steam for the metal to react with.
The Hydrogen gas produced is ignited to safely destroy it.

Question 18

Why do metals react with cold water and hot steam to produce different products?

Answer 18

Steam has more energy so both bonds in the water molecule can be broken: H2O—>H2 + O Water breaks one bond: H2O—>H+OH