How to calculate the no. of moles, molecules & total no. of atoms present in 1)1.1*10-4Kgof CO 2 , 2)5.6 cm2of Ammonia at STP, 3)0.4g of Helium gas
1) Molar mass of CO2 = 0.018 kg/mol
0.018 g of CO2 is present in one mole
1.1*10-4 kg is present in 1.1*10-4/0.018 = 0.006 mol
No of molecules in one mole = 6.022*1023
No of molecules in 0.006 mole = 0.006*6.022*1023 = 3.6*1021 molecules
No of atoms in one molecule of CO2 = 3
No of atoms in 3.6*1021 molecules of CO2 = 10.8*1021 atoms
2) Molar mass of NH3 = 0.017 kg/mol
22400 cm3 is occupied by one mole at STP
5.6 cm3 is occupied by 5.6/22400 = 0.00025 mol
No of molecules in one mole = 6.022*1023
No of molecules in 0.00025 mole = 0.00025*6.022*1023 = 1.5*1020 molecules
No of atoms in one molecule of NH3 = 4
No of atoms in 1.5*1020 molecules of NH3 = 6*1020 atoms
0.018 g of CO2 is present in one mole
1.1*10-4 kg is present in 1.1*10-4/0.018 = 0.006 mol
No of molecules in one mole = 6.022*1023
No of molecules in 0.006 mole = 0.006*6.022*1023 = 3.6*1021 molecules
No of atoms in one molecule of CO2 = 3
No of atoms in 3.6*1021 molecules of CO2 = 10.8*1021 atoms
2) Molar mass of NH3 = 0.017 kg/mol
22400 cm3 is occupied by one mole at STP
5.6 cm3 is occupied by 5.6/22400 = 0.00025 mol
No of molecules in one mole = 6.022*1023
No of molecules in 0.00025 mole = 0.00025*6.022*1023 = 1.5*1020 molecules
No of atoms in one molecule of NH3 = 4
No of atoms in 1.5*1020 molecules of NH3 = 6*1020 atoms