A-LevelChemistryChemical bonding9701/21 · May/June 2020 · Q46 Marks
Calcium nitrate, Ca(NO₃)₂, reacts with ammonia, carbon dioxide and water to form a mixture of ammonium nitrate and calcium carbonate. Ca(NO₃)₂ + 2NH₃ + CO₂ + H₂O → 2NH₄NO₃ + CaCO₃
- (a)Explain why ammonia is described as a Brønsted-Lowry base in this reaction.[1]
- (b)State two reasons why this mixture of products is added to some soils. 1 2[2]
- (c)Complete the table to name the shape and give the bond angle of each species. name of shape bond angle/° CO₂ NH₃ H₂O[3]
Mark scheme
Marking points from the official mark scheme (May/June 2020). The mark or mark type is shown in brackets.
- [1] Accepts a proton / H⁺ (ion)
- [M1] Acts as a fertiliser / adds nutrients (for plants)
- [M2] Neutralise acid soils / increases the pH of acid soil
- CO₂ Linear 180
- NH₃ Pyramid(al) 107
- H₂O non-linear / V / bent 104.5
- All 6 correct - 3 marks
- 4 or 5 correct - 2 marks
- 2 or 3 correct - 1 mark
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →