Molar Mass and Chemical Formulas

The video tutorial explains how to calculate the molar mass of nickel(II) nitrate hexahydrate, Ni(NO3)2.6H2O. It begins by identifying the molar masses of nickel, nitrogen, and oxygen from the periodic table. The tutorial then demonstrates how to multiply the molar mass of oxygen by three, as there are three oxygen atoms in the compound. Next, it adds the molar mass of six water molecules, considering the molar masses of hydrogen and oxygen. The final molar mass of the compound is calculated to be 228.82 grams per mole. The video concludes by noting that different periodic tables may yield slightly different results.

What is the chemical formula for nickel(II) nitrate hexahydrate?

• Ni(NO3)2.5H2O

• Ni(NO2)2.6H2O

• Ni(NO3)3.6H2O

• Ni(NO3)2.6H2O

What is the molar mass of nickel used in the calculation?

• 58.69 grams per mole

• 14.01 grams per mole

• 16.00 grams per mole

• 1.01 grams per mole

How many oxygen atoms are present in the nitrate component of Ni(NO3)2.6H2O?

• Two

• Six

• Four

• Three

What is the molar mass of hydrogen used in the calculation of water molecules?

• 58.69 grams per mole

• 1.01 grams per mole

• 14.01 grams per mole

• 16.00 grams per mole

How many water molecules are associated with each formula unit of Ni(NO3)2.6H2O?

• Six

• Two

• Three

• Four

What is the final calculated molar mass of Ni(NO3)2.6H2O?

• 228.82 grams per mole

• 200.00 grams per mole

• 250.00 grams per mole

• 180.00 grams per mole

Why might the calculated molar mass differ slightly when using different periodic tables?

• Due to different chemical reactions

• Due to incorrect chemical formulas

• Due to rounding differences

• Due to changes in temperature