The Mole (previous version): Its History and Use

The mole is also referred to as:

• a.Avogadro's number
• b.Bohr's number
• c.Cannizzaro's number
• d.Loschmidt's number

What number does the mole represent?

• a.12
• b.6 x 10²²
• c.6.02 x 10²³
• d.60.2 x 10²³

The concept of the mole says that:

• a.in a defined mass of an element there is a precise number of atoms
• b.in a defined mass of an element there is a precise number of compounds
• c.in the atomic weight of an element there is one atom
• d.none of the choices

How many silicon atoms are there in 28.09 g of Si?

• a.1
• b.1.204 x 10²⁴
• c.28.09
• d.6.02 x 10²³

How do you calculate the molecular weight of a compound?

• a.by dividing the weight of atoms of the compound
• b.by summing the atomic weights of elements in that compound
• c.by multiplying the weight of atoms of the compound
• d.by subtracting the weight of atoms of the compound

What is the molecular weight of CO₂?

• a.28.01
• b.32.00
• c.44.01
• d.72.08

Which one of the following has the same number of moles as 28.02 g of nitrogen?

• a.19.00g of potassium
• b.23.00g of potassium
• c.24.01g of magnesium
• d.36.04g of water