C22 - Further Periodicity

Question 1

What is the reaction of sodium with water?

Answer 1

Na + water = sodium hydroxide + hydrogen gas

This reaction produces a strong alkaline solution.

Question 2

What is the reaction of magnesium with water?

Answer 2

Mg + water = magnesium hydroxide + hydrogen gas

Magnesium hydroxide is also a weak base.

Question 3

What is the reaction of magnesium with steam?

Answer 3

Mg + steam = magnesium oxide + hydrogen gas

This reaction occurs at higher temperatures.

Question 4

What is the appearance magnesium oxide at room temperature?

Answer 4

Magnesium oxide is a white solid

It is a product of magnesium reacting with steam.

Question 5

What is the reaction of chlorine with water?

Answer 5

Cl2 + water = HCl + HClO

This reaction produces hydrochloric acid and hypochlorous acid.

Question 6

What color flame does sodium produce when burned in oxygen?

Answer 6

Orange

This is characteristic of sodium’s combustion.

Question 7

What product is formed when magnesium burns in oxygen?

Answer 7

Magnesium oxide

This product is a white solid.

Question 8

What is the flame color of sulfur when burned in oxygen?

Answer 8

Blue

This indicates the combustion of sulfur producing sulfur dioxide.

Question 9

What is the trend of pH in period 3 oxides?

Answer 9

Decreases from very alkaline with sodium oxide to very acidic with sulfur oxides

Aluminium and silicon oxides are insoluble, resulting in a neutral pH of 7.

Question 10

Which oxides in period 3 are ionic?

Answer 10

Sodium oxide, Magnesium oxide, Aluminium oxide

The rest of the oxides are covalent.

Question 11

What type of molecular structure does silicon dioxide have?

Answer 11

Macromolecular

This structure contributes to its insolubility.

Question 12

What is an amphoteric oxide?

Answer 12

An oxide that can act as both an acid and a base

Example: Aluminium oxide.

Question 13

How does silicon dioxide react with strong bases?

Answer 13

Reacts as a weak acid to produce salt and water

This is a characteristic behavior of silicon dioxide.

Question 14

What is the product formed when phosphorus burns in oxygen?

Answer 14

Phosphorus oxide (P4O10)

It is a white solid formed from the combustion of phosphorus.

Question 15

What is the trend in melting points for period 3 oxides?

Answer 15

Increase from sodium to magnesium before falling for the rest of the period with SO2 being the lowest