Alcohol of mass 21g and density 0.7g cm-3 is mixed with 10g of water. Determine the density of the mixture [density of water = 1.0gcm-3]
A
0.775gcm-3
B
0.875gcm-3
C
0.780gcm-3
D
0.880gcm-3
Verified Correct Answer: A.
Physical Principles & Numerical Solution
\(V_A = \frac{M}{D} = \frac{21}{0.7} = 30cm^3\)
\(V_w = \frac{M}{D} = \frac{10}{1} = 10cm^3\)
Vmixture = 30 + 10 = 40cm3
Mmixture = 21 + 10 = 31g
Dmixture = \(\frac{m}{v} = \frac{31}{40} = 0.775\)
Source: Myschool Past Questions Archive (Record #35748)