9.7 METALS AND WATER

Question 1

What metals react vigorously with cold water?

Answer 1

1. Sodium
2. Potassium
3. Calcium

Question 2

What metals react slowly with cold water?

Answer 2

1. Magnesium
2. Zinc
3. Iron

Question 3

How does sodium react with cold water?

Answer 3

1. When sodium touch the water, sodium zooms around, bubbling vigorously
2. React vigorously with water

Question 3

How does potassium react with cold water?

Answer 3

1. Reacts more vigorously than sodium. Reacting potassium gets hot enough to set fire to the hydrogen gas
2. React vigorously with water

Question 4

Potassium + water -> ?

Answer 4

potassium hydroxide + hydrogen

Question 5

Sodium + water -> ?

Answer 5

Sodium hydroxide + hydrogen

Question 6

How does calcium react with cold water?

Answer 6

1. When calcium drops into water, it bubbles quickly. Soon, the bubbling stops. Calcium disappeared.
2. React more vigorously with water

Question 7

Calcium + water -> ?

Answer 7

Calcium hydroxide + hydrogen

Question 8

How do we test if hydroxide is alkaline?

Answer 8

1. test with universal indicator
2. Becomes purple = alkaline

Question 9

How does magnesium react with cold water?

Answer 9

1. A few bubbles of hydrogen form

Question 9

How do we test hydrogen?

Answer 9

1. Test with lighted splint
2. Goes out with a squeaky pop

Question 10

Magnesium + water -> ?

Answer 10

magnesium hydroxide + hydrogen

Question 11

How does zinc react with cold water?

Answer 11

Do not react with water, but react with steam (water in gas state)

Question 12

Zinc + water (as steam) -> ?

Answer 12

zinc oxide + hydrogen

Question 13

How does iron react with cold water?

Answer 13

Do not reach with water alone, it corrodes with water and oxygen to make rust (iron oxide)

Question 14

What are the metals that don’t react with water?

Answer 14

1. Copper
2. Silver
3. Gold