Question

A 4L beaker of mercury Hg#80 (density 13.59g/ml) has a weight of how many a) grams and b)lbs.?

Answer 1

WE just need to apply the formula of the density:

$\rho=\frac{m}{V}$

where p is the density, m is the mass and V is the volume, in this case they are asking about the mass so we have to solve that equation for the mass:

$m=\rho\times V=\text{ 4000ml }\times13.59\text{ }\frac{g}{ml}=54360g$

Please notice that to solve that question every thing has to be in the same units

To transform grams into pounds we need to know that 1 pound is 456.6 grams and use this information as conversion factor:

$54360\text{ grams}\times\frac{1lb}{453.6\text{ grams}}=119.8lb$