Which contains more atoms, 1 mol of helium or 1 mol of uranium? Which has a greater mass? [ RAM: He=4; U=238 ]
1 mol of helium and 1 mol of uranium has equal number of atoms.
The mass of one Uranium atom ss greater than the mass of one helium atom.
Find the number of atoms in 2.5 mol of gold.
Number of atoms
= Number of mole x Avogadro constant
= 2.5 x 6.02 x 1023 = 1.505 x 1024
How many moles of magnesium that contain 2.76 x 1023 of magnesium atom?
Number of mole
= Number of atoms ÷ Avogadro constant
= 2.76 x 1023 ÷ 6.02 x 1023
= 0.46 mol
Each hydrogen molecules (H2) consist of 2 hydrogen atoms.
Therefore, 20 mol of hydrogen atoms can make 10 mole of hydrogen molecules.
b. Number of mole of hydrogen atoms in 20 mole of hydrogen molecules
= 2 x 20 mole = 40 mole.
Each carbon dioxide molecules (CO2) consist of 1 carbon atom and 2 oxygen molecules.
Therefore, 0.75 mole of carbon dioxide contain 0.75 mole carbon atoms.
Number of mole of oxygen atoms in 0.75 mole of carbon dioxide
= 2 x 0.75 mole = 1.50 moles.