Periodicity

Question 1

What’s the equation for the reaction of sodium with water?

Answer 1

2Na + H2O –> 2NaOH + H2

Question 2

What’s the equation for the reaction of sodium with Oxygen?

Answer 2

2Na + 1/2O2 –> Na2O

Question 3

What is the ionic equation for the reaction of Na2O with water?

Answer 3

Na2O(s) + H2O(l) –> 2Na+(aq) + 2OH-(aq)

Question 4

What is the pH of the solution formed from the reaction of Na2O with water?

Answer 4

13

Question 5

How far (if at all) does NaOH dissociate in water?

Answer 5

fully

Question 6

What’s the equation for the reaction of magnesium with water?

Answer 6

Mg + 2H2O –> Mg(OH)2 + H2

Question 7

What’s the equation for the reaction of magnesium with steam?

Answer 7

Mg(s) + 2H2O(g) –> MgO(s) + H2(g)

Question 8

What’s the equation for the reaction of magnesium with oxygen?

Answer 8

2Mg + O2 –> 2MgO

Question 9

What’s the equation for the reaction of magnesium oxide with water?

Answer 9

MgO(s) +H2O(l) –> Mg(OH)2(aq)

Question 10

What’s the pH of the solution formed from the reaction magnesium oxide with water?

Answer 10

8

Question 11

How far (if at all) does Mg(OH)2 dissociate in water?

Answer 11

partially

Question 12

Why does MgO not dissolve in water as much as Na2O?

Answer 12

Because MgO has stronger ionic bonds.

Question 13

Why does the reaction of MgO with water produce a lower pH solution than that of the reaction of Na2O with water?

Answer 13

Because Mg(OH)2 is not as soluble as NaOH

Question 14

Describe something odd about the nature of the ionic bonds formed with Al3+ ions.

Answer 14

They have covalent character

Question 15

What’s the equation of Al with oxygen?

Answer 15

4Al + 3O2 –> 2Al2O3

Question 16

What is the pH achieved when Al2O3 is added to pure water?

Answer 16

7

Question 17

What is the equation for the reaction of Si with oxygen?

Answer 17

Si + O2 –> SiO2

Question 18

Is silicon dioxide soluble in water?

Answer 18

No

Question 19

What is the equation for the reaction of phosphorous with oxygen?

Answer 19

P4 + 5O2 –> P4O10

Question 20

What are the equations for the reaction of sulfur with oxygen? (there are two)

Answer 20

S + O2 –> SO2
S + 1 1/2 O2 –> SiO3

Question 21

What is the equation for the reaction P4O10 with water?

Answer 21

P4O10 + 6H2O –> 4H3PO4

Question 22

What is the pH of the solution formed from the reaction of P4O10 with water?

Answer 22

1-2

Question 23

What is interesting about the nature of Al2O3?

Answer 23

it is amploteric (can act as an acid or base)

Question 24

What is the equation for the reaction of Al2O3 with alkaline NaOH?

Answer 24

Al2O3(s) + 2NaOH + 3H2O –> 2NaAl(OH)4(aq)

Question 25

What is the equation for the reaction of Al2O3 with acidic HCl?

Answer 25

Al2O3(s) + 6HCl(aq) --> AlCl3(aq) +3H2O(l)

Question 26

What is the equation for the reaction of SO2 with water?

Answer 26

SO2 + H2O --> H2SO3 (sulfurous acid)

Question 27

What is the pH achieved by the reaction of SO2 with water?

Answer 27

2-3

Question 28

What is the equation for the reaction of SO3 with water?

Answer 28

SO3 + H2O --> H2SO4 (sulfuric acid)

Question 29

What is the pH achieved from the reaction of SO3 with water?

Answer 29

1

Question 30

Which dissociated more easily SO2 or SO3?

Answer 30

SO3

Question 31

What is the equation for the reaction of Chlorine with water?

Answer 31

Cl2 + H2O --> HCl + HOCl

Question 32

What type of reaction is the reaction of chlorine with water?

Answer 32

Disproportionation reaction

Question 33

What is disproportionation reaction?

Answer 33

A reaction where one thing is both oxidised and reduced

Question 34

What is the equation for the oxidation of Cl2 when it reacts with water?

Answer 34

Cl2 + 2e- --> 2Cl-

Question 35

What is the equation for the reduction of Cl2 when it reacts with water?

Answer 35

Cl2 + 2H2O --> 2HOCl + 2H+ + 2e-