Question

What is the number of representative particles in .400 mol `KCl`?

Answer 1

There are `0.4` `xx` `N_A` potassium cations, and an equal quantity of chloride anions.

Explanation:

But what is `N_A`? `N_A` is simply `"Avogadro's number"`, `6.022140857 × 10^23`. This number has the property that `N_A` `""^12C` atoms has a mass of `12.00` `g` precisely. `N_A` is thus the link between atoms and molecules, about which we can only conceive, and the macro world of grams and kilograms, and litres, that which we can measure in a laboratory.

What is the mass of `0.400` `mol` `KCl`, given that `KCl` has a mass of `74.55*g*mol^-1`?