2018 · Q4
Which of the following characteristics is common to hydrogen, nitrogen, oxygen and carbon dioxide?
General KnowledgeChemistry
- AThey are all diatomic.
- BThey are all gases at room temperature.
- CThey are all coloured.
- DThey all have same reactivity.
Explanation
Hydrogen, nitrogen, oxygen and carbon dioxide are all gases at room temperature (around 25 degC). They are not all diatomic, since CO2 is a triatomic molecule. They are all colourless, not coloured, and their chemical reactivities differ greatly (nitrogen is inert while oxygen is highly reactive). The only characteristic shared by all four is the gaseous state at room temperature.