Properties Of Period 3 Elements And Their Oxides

Question 1

What is the equation for when Sodium reacts with water?

Question 2

What is the equation for when Magnesium reacts with water ?

Question 3

Explain the trend in reactivity of period 3 elements

Question 4

Describe the trend in melting points across period 3 elements

Answer 4

Na2O, MgO and Al2O3 - have high melting points sure to the ionic bonding, held together by strong electrostatic forces forces between negative oxygen ions and positive metal ions

MgO and Al2O3 > Na2O contain metals with higher charges

SiO2 very high melting point due to its giant covalent structure (macromolecular lattice), these covalent bonds require A-LOT of energy in order to break the bonds

P4O10, SO2 and SO3 have low melting as they are simple molecular structures with weak intermolecular forces that therefore do not require much energy to overcome the bond

Question 5

What are the formulas for the oxides formed across period 3?

Answer 5

Na2O
MgO
Al2O3
SiO2
P4O10 or P4O6
SO2 or SO3

Question 6

Why are the reaction of period 3 oxides with water? (Na to S)

Question 7

What happens to the pH of the solutions formed when the period 3 oxides react with water?

Question 8

What is the structure of acid formed when P4O10 reacts with water?

Question 9

What is the structure of the acid formed when SO2 reacts with water ?

Question 10

What is the structure of the acid formed when SO3 reacts with water?