2.5 litre of 1M NaOH solution is mixed with a 3.0 litres of 0.5 M NaOH solution. The molarity of the resulting solution is :
A. 0.80 M
B. 1.0 M
C. 0.73 M
D. 0.50 M.
Correct Answer - D
Molarity = `(W_(2)/(M_(2) xxV(dm^(3))))`
`=(5g)/(40 g "mol"^(-1) xx V("dm")^(3))`
`=1.25 mol dm^(-3)` (`therefore 100 mL = 0.1 L = 0.1 dm^(3))`
Calculation of molarity of the solution
Mass of NaOH =4g, Molar mass of NaoH=40 g `mol^(-1)`
Volume of solution=1 decilitre=0.1L
Molarity (M)`=("Mass of NaOH"//"Molar mass of NaOH")/("Volme of solution in...