If you mixed 80 tons of sand, 12 tons of rock, and 4.0 tons of cement to make concrete, what would the percent by weight of sand be?

Every time a problem asks you to find the of a substance, your goal will essentially be to determine the mass of one unit of volume of said substance....

Density is the amount of matter within a specific volume. As a trend, some Solids tend to be more dense than liquids and will sink. For example, Lead has a...

The ($ρ$) of anything is its mass ($m$) divided by its volume ($V$). $color(blue)(bar(ul(|color(white)(a/a)ρ = m/Vcolor(white)(a/a)|)))" "$ The volume of the rock is equal to the...

The of the rock essentially tells you the mass of one unit of volume of that rock. In this case, a density of $"4 g/mL"$ means that $"1 mL"$...

$rho="Mass"/"Volume"=(16*g)/(8*cm^-3)$ $=$ $??*g*cm^-3$ And the volume of each piece is $??*cm^3$.

$"Density"$ $=$ $"Mass"/"Volume"$, i.e. mass per unit volume, and it typically has units of $g*mL^-1$ or $g*cm^-3$. If your rock has a VOLUME of $4*mL$ and a MASS of $16*g$,...

Density is by definition mass divided by volume.

$"Density, "rho="Mass"/"Volume"$. And thus with the given units, we simply set up this quotient: $"Mass"/"Volume"=(14*g)/(2*cm^3)$, and $rho=??$; and you can see that this quotient gives the required units of $g*cm^-3-=g*mL^-1$....

The sieve will allow all of the sand to pass right through it, while catching the seashells.

She got $60*g$ of mercury metal....this represents a molar quantity of $(60*g)/(200.6*g*mol^-1)=0.299*mol$ with RESPECT to the metal. And thus there were $0.299*mol$ with respect to mercuric oxide... $HgO(s) + Delta...