Question

How many equivalents of thiamine hydrochloride are used when 1.50 g of thiamine hydrochloride are mixed with 4.5 ml of benzaldehyde? Report your answer using the correct number of significant figures.

A. 0.005

B. 0.01

C. 0.02

D. 0.03

Answer 1

To find the number of equivalents of thiamine hydrochloride used, calculate the number of moles of thiamine hydrochloride using its molar mass and then convert that to equivalents using the stoichiometry of the reaction. The correct answer is B. 0.01.

Step-by-step explanation:

To find the number of equivalents of thiamine hydrochloride used, we need to calculate the number of moles of thiamine hydrochloride using its molar mass and then convert that to equivalents using the stoichiometry of the reaction. The molar mass of thiamine hydrochloride (C12H17N4OSCl) is 337.27 g/mol.

Step 1: Calculate the number of moles of thiamine hydrochloride: 1.50 g / 337.27 g/mol = 0.00445 mol

Step 2: Convert moles to equivalents. Since thiamine hydrochloride is a monoprotic acid, 1 mole of thiamine hydrochloride is equal to 1 equivalent. Therefore, 0.00445 mol of thiamine hydrochloride is equal to 0.00445 equivalents.

The correct answer is B. 0.01, as it is the closest option to the calculated value of 0.00445 equivalents.