2. Atoms & Elements

How many moles of nitrogen atoms (N) are present in 0.207 g of N_2O?

What is the total number of atoms contained in a 1.00-mole sample of helium (He)?

How many moles of MgCO_3 are present in 252.939 grams of MgCO_3?

How many moles of chlorine gas (Cl_2) are contained in 9.02 × 10^{23} molecules?

How many water molecules are present in 5.2 moles of H_2O?

In chemistry, what does a mole represent?

Which of the following samples contains the greatest number of moles?

How many moles are present in 17.5 grams of sodium (Na)? (Atomic mass of Na = 23.0 g/mol)

Which proportionality correctly describes Avogadro's law?

How many atoms of carbon are present in 0.68 moles of carbon?

In which of the following situations is the mole concept most likely to be used?

How many moles are present in 3.01 × 10^{23} molecules of H_2O?

Which of the following masses represents 0.500 mol of NaCl?

How many atoms are present in 3 moles of carbon?

How many atoms are present in one mole of any element?