Mole Concept and Avogadro Constant

Chemistry ⇒ Stoichiometry and Chemical Calculations

Mole Concept and Avogadro Constant starts at 9 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Mole Concept and Avogadro Constant. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 10

A chemist has 0.1 moles of sodium atoms. How many sodium atoms does she have?

A sample contains 1.204 \times 10^{24} molecules of CO_2. How many moles of CO_2 are present?

A sample contains 3.011 \times 10^{23} molecules of ammonia (NH_3). How many moles of NH_3 are present?

A sample of calcium carbonate (CaCO_3) weighs 100 g. (Molar mass = 100 g/mol) How many moles are present?

Calculate the number of molecules in 2 moles of water (H_2O).

Calculate the number of moles in 12.04 \times 10^{23} molecules of methane (CH_4).

Calculate the number of moles in 36 g of water (H_2O). (Molar mass of H_2O = 18 g/mol)

Explain why the mole is a useful unit in chemistry.

How many atoms are present in 3 moles of oxygen gas (O_2)?

How many atoms are there in 1 mole of magnesium (Mg)?

How many molecules are present in 0.25 moles of nitrogen gas (N_2)?

How many moles are present in 44 g of CO_2? (Molar mass of CO_2 = 44 g/mol)

If you have 0.5 moles of sulfur atoms, how many atoms do you have?

If you have 1 mole of Cl_2 molecules, how many chlorine atoms do you have?

If you have 4.5 moles of glucose (C_6H_{12}O_6), how many molecules do you have?

The molar mass of sodium chloride (NaCl) is 58.5 g/mol. How many moles are present in 117 g of NaCl?

What is the value of Avogadro's constant?

A chemist has 2.5 \times 10^{24} molecules of oxygen gas (O_2). Calculate the number of moles of O_2 molecules present. (Avogadro constant = 6.022 \times 10^{23} mol^{-1})

A sample contains 0.75 moles of aluminum atoms. Calculate the number of atoms present in the sample. (Avogadro constant = 6.022 \times 10^{23} mol^{-1})

A sample of a compound contains 1.8066 \times 10^{24} molecules. If the molar mass of the compound is 60 g/mol, what is the mass of the sample? (Avogadro constant = 6.022 \times 10^{23} mol^{-1})