2.4 Period 3

Question 1

What colour are most period 3 oxides?

Answer 1

White powder

Question 2

What colour is sodium oxide?

Answer 2

Yellow

Question 3

What colour is sulfur dioxide?

Answer 3

Blue

Question 4

What colours do most oxides burn?

Answer 4

White flame

Question 5

What colour does Na burn?

Answer 5

Orange flame

Question 6

What colour does S burn?

Answer 6

Blue flames
Choking gas

Question 7

Why does silicon have a higher melting point?

Answer 7

Giant covalent structure so high energy is needed to break the many strong covalent bonds

Question 8

What is the equation for sodium + water?

Answer 8

2Na + 2H2O —> 2NaOH + H2

Question 9

What is the equation for Phosphorous oxide + Water?

Answer 9

P4O10 + 6H2O —> 4H3PO4

Question 10

What does amphoteric mean?

Answer 10

Reacts with both acids and alkalis

Question 11

What is the equation for the reaction between Sodium oxide and water?

Answer 11

Na2O + H2O —> 2NaOH

Question 12

What is the reaction between Al2O3 + NaOH?

Answer 12

Al2O3 + NaOH —> 2NaAlO2 + H2O

Question 13

What is the reaction between aluminium oxide + nitric acid?

Answer 13

Al2O3 + 3HNO3 —> Al(NO3)3 + H2O

Question 14

Why is NaOH melting point lower than Mg(OH)2?

Answer 14

NaOH has a bigger atomic radius so has less attraction between the molecules, there is also less OH- ions to form bonds with.

Question 15

Why does aluminium have some covalent character?

Answer 15

The oxide has a similar EN so the ion distorts and has some covalent character

Question 16

How can substances be tested for containing ions?

Answer 16

By melting the substances and show they conduct electricity