Period 3 Elements

Question 1

Why is sodium more reactive than magnesium?

Answer 1

Sodium is more reactive than magnesium because it takes less energy to lose one electron than to lose two.

Question 2

Describe what happens when sodium reacts with water?

Answer 2

Sodium reacts vigorously with COLD water, forming a molten ball on the surface, fizzing and producing H2 gas.

Question 3

What is produced when sodium reacts with water?

Answer 3

Sodium hydroxide.
Strong alkaline solution (pH 12-14) is made.
2Na + 2H2O —> 2NaOH + H2

Question 4

Describe what happens when magnesium reacts with water?

Answer 4

Magnesium reacts slowly with COLD water, forming a thin coating of magnesium hydroxide on the surface of the metal.

Question 5

Describe what happens when magnesium reacts with steam?

Answer 5

Magnesium reacts fast with steam to form magnesium oxide.

Question 6

What is produced when magnesium reacts with water?

Answer 6

Magnesium hydroxide
Alkaline solution (pH9-12)
Mg + 2H2O —> Mg(OH)2 + H2

Question 7

What is produced when magnesium reacts with steam?

Answer 7

Magnesium oxide

Mg + H2O —> MgO + H2