The solubility in mol/dm3 of 20.2g of potassium trioxonitrate(V)dissolved in 100g of water at room temperature is

Explanation:

Potassium trioxonitrate(V) is KNO₃.

1. Find the molar mass of the solute

The molar mass of KNO₃ is 39.098g/mol + 14.007g/mol + 3×15.999g/mol = 101.102g/mol.

2. Convert the mass of solute, 20.02g, into number of moles

3. Assume that the volume of the solution is equal to the volume of water

This is a rough approximation, but it is necessary since you do not have the density of the solution:

Convert 100cm³ to dm³:

4. Calculate the solubility is mol/dm³

It is rounded to three significant digits to match the choices.

i believe the answer is three water molecules