Q6(b). Specific gravity of the acid as a test of the cell
Specific gravity of the sulfuric acid used in a lead acid storage cell gives an assessment about the performance of the cell — justify or criticise.
Answer in brief
Justified as a measure of the state of charge: discharge uses up H₂SO₄, so the specific gravity falls in step with the charge drawn; it does not test the health or capacity of the cell.
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Coverslead–acid batteryspecific gravityhydrometerstate of chargesulfuric acid
All parts of Question 6
- 6(a) Lead–acid cell: electrode and cell reactions on discharge6 marks
- 6(b) Specific gravity of the acid as a test of the cell4 marks