Chemical Calculations

Mole-Mass Calculation - Number of Moles = known mass of substance/ Molar mass of substance.

if moles are given we can find out the mass of an atom as well.

Mass of substance= Number of moles x Molar Mas

e.g.: A coin of silver (Ag) having 8.5 gm weight. Calculate the number of moles of silver in coin?

Number of Moles = known mass of substance/ Molar mass of substance

8.5/107

= 0.07 moles of silver in 8.5 gm silver coin

Mole-Particle Calculation - Number of Moles= Given number of particles/ $6.02*10^23$

by this formula we can find out the number of particles as well

Number of particles = Number of moles/ $6.02*10^23$

• Mole Volume Calculation - According to Avogadro, one gram mole of any gas at STP occupies volume of $22.4dm^3$