Question

A saline solution contains 0.90g of sodium chloride dissolved in 250 cm3 water

(a)what is the amount in moles of sodium chloride dissolved?
(b) the concentration of the saline solution in mol/dm3?

Answer 1

Step-by-step explanation:

A. mole=mass/molar mass

Molar mass of NaCl=23+35.5g

NaCl=58.5g

from

mole=0.90/58.5mol

mole=0.90g/58.5mol

mole=0.15

B. concentration=number of moles of solute/volume of solution

concentration=0.15mol/250cm^3

1dm^3=1000cm^3

250=0.25

concentration=0.6mol/dm^3