Question

A solution is prepared by adding $5g$ of a solute ${}^{\prime }{X}^{\prime }$ to $45g$ of solvent ${}^{\prime }{Y}^{\prime }$. What is the mass percent of solute ${}^{\prime }{X}^{\prime }$?

• A. $10\%$
• B. $11.1\%$
• C. $90\%$
• D. $75\%$

Answer 1

Answer: (A)

$10\%$

In a mixture of X and Y,

Mass % of X=$\frac{MassofX}{(MassofX+MassofY)}\times 100$

$\therefore$ mass % of X=$\frac{5}{5+45}\times 100=10$ %