IB myp 4-5 Chemistry – Practice Questions- All Topics
Topic :Periodic Table-Metals and Non-Metals
Topic :Periodic Table- Weightage : 21 %
All Questions for Topic : Metals and Non metals,Transition metals,Noble gases,Periodic trend groups and periods
Question : Periodic Table – Metals and Non-metals
Question a [4 marks]
State two properties each for:
- Aluminium
- Carbon
▶️ Answer/Explanation
a) Aluminium:
1. Malleable
2. Corrosion resistant
b) Carbon:
1. High strength-to-weight ratio
2. Does not react easily
Question b [1 mark]
Describe what happens when scandium reacts with air or water.
▶️ Answer/Explanation
Reaction with Air
When scandium is heated in air, it reacts with oxygen to form scandium(III) oxide, \( \text{Sc}_2\text{O}_3 \).
$
4\text{Sc (s)} + 3\text{O}_2 (g) \rightarrow 2\text{Sc}_2\text{O}_3 (s)
$
Reaction with Water
Scandium reacts slowly with cold water, but more rapidly with steam, producing scandium(III) hydroxide, \( \text{Sc(OH)}_3 \), and hydrogen gas.
$
2\text{Sc (s)} + 6\text{H}_2\text{O (l)} \rightarrow 2\text{Sc(OH)}_3 (s) + 3\text{H}_2 (g)
$
Question c [2 marks]
Explain why scandium is added to aluminium alloys.
▶️ Answer/Explanation
Scandium increases the yield strength of aluminium alloys.