2. Atoms & Elements

Which of the following best defines a mole in chemistry?

How many moles of ethane (C_2H_6) are present in 30 grams of ethane?

Which value represents the number of particles in 1 mol of a substance?

How many moles of carbon atoms are present in 1 mole of carbon dioxide (CO_2)?

How many molecules of nitrogen monoxide (NO) are present in a 22.5 g sample?

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

How many molecules are present in $0.500$ mole of $N_2{O}_5$? (Use $N_A=6.022\times {10}^{23}$ molecules/mol.)

If you have 2 moles of Li, how many atoms of lithium do you have?

Which of the following is equivalent to a mole of carbon atoms?

In chemistry, what does one mole represent?

Why do chemists prefer using the mole instead of counting individual particles?

How many total atoms are present in 3 Na_2SO_4?

If you have 124 grams of sodium oxide (Na2O), how many moles of sodium oxide do you have?

Which equation correctly relates the number of moles of a solute (n) to its mass (m) and molar mass (M)?

How many atoms are present in 3 moles of chromium (Cr)?