Question

Calculate the molarity of 1.60 L of a solution containing 8.53 g of dissolved KBr.

Answer 1

0.044 M is the molarity of 1.60 L of a solution containing 8.53 g of dissolved KBr.

Explanation:

Data given:

volume of the solution = 1.60 litres

mass of KBr  = 8.53 grams

atomic mass of KBr = 119.002 gram/moles (K = 39.09 g/mole + 79.9 g/mole)

number of moles =?

molarity of KBr solution =?

First the number of moles will be calculated by using the formula:

number of moles = $\frac{mass}{atomic mass of 1 mole}$

putting the values in the equation:

number of moles = $\frac{8.53}{119.002}$

number of moles = 0.071 moles of KBr

now molarity is calculated using the formula:

molarity = $\frac{number of moles}{volume in litres}$

putting the values in the equation:

molarity = $\frac{0.071}{1.6}$

              = 0.044 M

molarity of KBr solution is 0.044 M