Question

Brine has a density of 1.2 g/cc. 40 cc of it is mixed with 30 cc of water. The density of the resulting solution will be

• A. $2.11$ g/cc
• B. $1.11$ g/cc
• C. $12.2$ g/cc
• D. $20.4$ g/cc

Answer 1

Answer: (B)

$1.11$ g/cc

Density of Brine$={\rho }_b=1.2g/cc$

Volume of Brine$=v_b=40cc$

Mass of Brine$=m_b={\rho }_b\times v_b=1.2\times 40=48g$

Density of Water$={\rho }_w=1g/cc$

Volume of Water$=v_w=30cc$

Mass of Water$=m_w={\rho }_w\times v_w=1\times 30=30g$

Density of mixture$=\frac{\text{Mass of mixture}}{\text{Volume of mixture}}=\frac{m_b+m_w}{v_b+v_w}=\frac{48+30}{40+30}=\frac{78}{70}=1.11g/cc$