Covalent and dative covalent bondingAQA A-Level Chemistry: Mind map

Exam questions on Covalent and dative covalent bonding

1. Nitrogen gas from the air is used to make ammonia. Ammonia is then converted into fertilisers that contain the ammonium ion, NH₄⁺.
   Explain how an ammonia molecule forms an ammonium ion with a hydrogen ion, H⁺.2 marks
2. Carbon monoxide, CO, is a toxic gas formed by the incomplete combustion of carbon-containing fuels. A carbon atom has four outer-shell electrons and an oxygen atom has six. In carbon monoxide the carbon and oxygen atoms are joined by a triple bond, and each atom has one lone pair of electrons.
   Explain why one of the bonds in carbon monoxide is a dative covalent bond, and state how this bond is represented in a displayed formula.2 marks
3. Boron trifluoride, BF₃, is a gas in which the boron atom has only six electrons in its outer shell. It reacts with ammonia, NH₃, to form a solid compound with the formula H₃N→BF₃.
   Explain how the bond between the nitrogen atom and the boron atom forms.3 marks