Question

the density of ethanol, a colorless liquid that is commonly known as grain alcohol, is 0.798 $\frac{g}{ml}$. calculate the mass of 21.8 ml of the liquid in grams. be sure your answer has the correct number of significant digits.

Explanation:

Step1: Recall density formula

Density ($
ho$) = $\frac{mass(m)}{volume(V)}$, so $m=
ho\times V$.

Step2: Identify given values

$
ho = 0.798\frac{g}{mL}$, $V = 21.8mL$.

Step3: Calculate mass

$m=0.798\frac{g}{mL}\times21.8mL$.
$m = 0.798\times21.8g$.
$m=17.4g$ (rounded to 3 significant digits).

Answer:

17.4 g