The molecular mass of sulphuric acid is 98. If 49 g of the acid is dissolved in water to make one litre of solution, what will be the strength of the acid?

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Q: 44 (CDS-I/2017)
The molecular mass of sulphuric acid is 98. If 49 g of the acid is dissolved in water to make one litre of solution, what will be the strength of the acid?

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,3,12,6,3,5,1

keywords: 

{'sulphuric acid': [1, 1, 0, 1], 'molecular mass': [0, 0, 0, 1], 'litre': [2, 1, 1, 4], 'acid': [2, 1, 4, 16], 'strength': [2, 0, 0, 2], 'solution': [2, 0, 7, 14]}

The question asks about the strength of the sulphuric acid solution, given its molecular mass and concentration. The molecular mass of sulphuric acid is 98 g/mol. If 49 g of the acid is dissolved in one litre of water, this means that the concentration of the acid in the solution is 49 g/L.

To determine the strength of the acid, we need to determine the number of equivalents present in the solution. Sulphuric acid is a diprotic acid, meaning it can donate two protons (H+) per molecule. Therefore, the number of equivalents of the acid is twice the number of moles present.

To calculate the number of moles of sulphuric acid, we divide the mass of the acid by its molar mass: 49 g / (98 g/mol) = 0.5 mol. Since there are two moles of protons per mole of acid, the number of equivalents is 2 * 0.5 = 1 equivalent.

Therefore, the strength of the sulphuric acid solution is one normal.

Option 2 is the correct answer.

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