Answer
a. 0.28 $cm^{3}$
b. 49 carats.
Work Step by Step
a) Density = $3.51 g/cm^{3}$
Mass = 5.0 carats = $5.0 carat \times \frac{0.200g}{1 carat}$ = 1.0 g
Volume = Mass/Density = $\frac{1.0g}{3.51 \frac{g}{cm^{3}}}$ = 0.28 $cm^{3}$
b) Volume = 2.8 mL
Density = 3.51 g/mL
Mass = $Volume\times Density = 2.8 mL\times 3.51 g/mL$ = 9.8 g
= $9.8 g\times\frac{1carat}{0.200g}$ = 49 carats.
