Question

The mass and volume of a body are 4.237 g and 2.5 cm3, respectively. The density of the material of the body in correct significant figures is

• A. $1.7gc{m}^{-3}$
• B. $1.69gc{m}^{-3}$
• C. $1.695gc{m}^{-3}$
• D. $1.6048gc{m}^{-3}$

Answer 1

The correct option is A $1.7gc{m}^{-3}$

Given: Mass of body (m) = 4.237 g
Volume of body $\left(V\right)=2.5c{m}^3$
As we know, Density $\rho =\frac{\text{m}ass\left(m\right)}{\text{V}olume\left(V\right)}$
Therefore, Density $\rho =\frac{4.237g}{2.5c{m}^3}$
Density $\rho =1.6948\frac{g}{c{m}^3}$

According to the rules of significant figures, while division of numbers, the final answer should have least number of significant figures.As the mass has 4 significant figures and volume has 2 significant figures, therefore, as per rule, density will have only two significant figures. Rounding off to two significant figures, we get, $\rho =1.7gc{m}^{-3}$

Final Answer: (c) $1.7gc{m}^{-3}$