QUESTION - What is the total weight, in pounds, of $1$ cubic meter of an ideal soil including the soil solution. You can assume that the particle density of the soil solids = $2.65$ Mg/cubic meter and that the density of soil solution= $1$ g/cubic cm.
so I already converted the density of soil solution to be $0.0001$ Mg/cubic meter, and I know that density = mass $\times$ volume, but I am not sure how to do the next part. I know that ideal soil is $25\%$ soil solution, $25\%$ soil atmosphere and $50\%$ soil solids.
The density of soil solution is wrong: $$1\frac {\rm g}{\rm cm^3}=\frac {1\rm g}{(1\rm cm)^3}=\frac{1\rm g}{(10^{-2}\rm m)^3}=\frac{1\rm g}{10^{-6}\rm m^3}=1\frac{\rm Mg}{\rm m^3}$$
In the ideal soil you have $25\%$ solution, and $50\%$ solid, so the density of the two together is $$0.25\cdot 1\frac{\rm Mg}{\rm m^3}+0.5\cdot 2.65\frac{\rm Mg}{\rm m^3}$$ Therefore one cubic meter of soil will weigh $1.575\rm{Mg}$. You just need to transform this to pounds.