Which of the following statements about nitrogen or its compounds is correct?
- AIn the Haber process the temperature is kept high to give a good equilibrium yield of ammonia.
- BNitrogen gas is unreactive because of the strong nitrogen-nitrogen double bond.
- CNitrogen monoxide will react with carbon monoxide under suitable conditions.
- DThe formula of ammonium sulfate is $\text{NH}_4\text{SO}_4$.