✔ 最佳答案
Explain why 1 mole of magnesium atoms is twice the mass of 1 mole of carbon atoms.
Mass of 1 mole of Mg atoms
= Molar mass of Mg atoms
= 24 g mol-1
Mass of 1 mole of C atoms
= Molar mass of C atoms
= 12 g mol-1
24 g mol-1 is twice of 12 g mol-1.
Therefore, the mass of 1 mole of Mg atoms is twice the mass of 1 mole of C atoms.
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What mass of magnesium contains the same number of atoms as 12 g of carbon?
Mg contains the same number of atoms as 12 g of C if they have the same number of moles of atoms.
No. of moles of C = mass/(molar mass) = 12/12 = 1 mol
No.of moles of Mg = No. of moles of C = 1 mol
Mass of Mg = (molar mass) x mol = 24 x 1 = 24 g
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What mass of oxygen contains the same number of molecules as 56 g of nitrogen?
O2 contains the same number of molecules as 56 g of N2 if they have the same number of moles of molecules.
No. of moles of N2 = mass/molar mass = 56/28 = 2 mol
No. of moles of O2 = No. of moles of N2 = 2 mol
Mass of O2 = (molar mass) x mol = 32 x 2 = 64 g
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What mass of chlorine contains the same number of molecules as 36g of water?
Cl2 contains the same number of molecules of 36 g of H2O if they have the same number of moles of molecules.
No. of moles of H2O = mass/molar mass = 36/18 = 2 mol
No. of moles of Cl2 = No. of moles of H2O = 2 mol
Mass of Cl2 = (molar mass) x mol = 71 x 2 = 142 g
