Question

What mass of salt is contained in a `200*mL` volume of solution that is `0.10*mol*L^-1` with respect to `KCl(aq)`?

Answer 1

Approx. `1.5*g` with respect to the salt.....

Explanation:

By definition, `"concentration"="quantity of stuff (mole or grams)"/"volume of solution"`

We have `200*mL` volume of `KCl(aq)` that is `0.1*mol*L^-1` with respect to potassium chloride.....

And so we take the product, and remember that `1*mL-=1xx10^-3*L`, and so.....

`200*cancel(mL)xx0.10*mol*cancel(L^-1)xx10^-3*cancelL*cancel(mL^-1)=`

`=20.0xx10^-3*mol`

But potassium chloride has a molar mass of `74.55*g*mol^-1`

And so we got a mass of.....

`20.0xx10^-3*molxx74.55*g*mol^-1=??*g`