MEDIUM
Upper Secondary: IGCSE
IMPORTANT
Earn 100

Solid sodium chloride will not conduct electricity, but a solution of sodium chloride will conduct. Explain this.

Important Questions on Atoms Combining

HARD
Upper Secondary: IGCSE
IMPORTANT
A compound melts at 20 °C. What kind of structure do you think it has? Why do you think so?
MEDIUM
Upper Secondary: IGCSE
IMPORTANT
A compound melts at 20 °C. Will it conduct electricity at 25 °C? Give a reason.
HARD
Upper Secondary: IGCSE
IMPORTANT
Describe the arrangement of particles in ice. How will the arrangement change as the ice warms up?
HARD
Upper Secondary: IGCSE
IMPORTANT
The covalent compound ethanol melts at -114 °C. Is it a molecular compound, or a giant structure? Explain.
EASY
Upper Secondary: IGCSE
IMPORTANT
Diamond and graphite are allotropes of carbon. What does that mean?
MEDIUM
Upper Secondary: IGCSE
IMPORTANT
Why is diamond so hard?
HARD
Upper Secondary: IGCSE
IMPORTANT
Why diamond and graphite have such very different properties? Draw diagrams to explain.
MEDIUM
Upper Secondary: IGCSE
IMPORTANT
Explain why silica has high melting point.