2. Atoms & Elements

One mole of particles of any substance contains how many particles?

If you produced 5 moles of Ca3(PO4)2, how many moles of calcium ions (Ca^{2+}) are present?

How many molecules are present in 3.6 grams of NaCl?

How many moles are present in 2.5 g of N_2?

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?