GATE 2021 CH – Question 25
Match the common name of chemicals in Group – 1 with their chemical formulae in Group – 2.
| Group – 1 | Group – 2 |
|---|---|
| P: Gypsum | I: $\mathrm{Ca(H_2PO_4)_2}$ |
| Q: Dolomite | II: $\mathrm{CaSO_4\cdot2H_2O}$ |
| R: Triple superphosphate | III: $\mathrm{CaCO_3\cdot MgCO_3}$ |
The correct combination is:
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: (C) P–II, Q–III, R–I
Explanation
Check the three matches separately.
- **Gypsum** is calcium sulfate dihydrate, $\mathrm{CaSO_4\cdot2H_2O}$: **P–II**.
- **Dolomite** is calcium magnesium carbonate, written $\mathrm{CaCO_3\cdot MgCO_3}$: **Q–III**.
- **Triple superphosphate** is predominantly monocalcium phosphate, represented here by $\mathrm{Ca(H_2PO_4)_2}$: **R–I**.
All three pairs occur together only in **C**.