9.1&9.3

The number of representative particles in a mole, is called .......................................

• Atom.

• Molecule.

• Avogadro's number.

The mole allows chemists to count the number of representative particles in a substance.

• True

• False

How many moles of magnesium is 2.5 x 10²³ atoms of magnesium?

• 0.208 mole

• 0.416 mole

• 0.104 mole

Propane is a gas used for cooking and heating. How many atoms are in 1.06 mole of propane C₃H₈ ?(H=1, C=12)

• 1.4 x 10²⁵ atoms

• 7 x 10²⁴ atoms

• 1.4 x 10²³ atoms

The mass of a mole of an element is its molar mass.

• True

• False

What is the molar mass of water (H₂O)? {H = 1, O = 16}

• 17

• 18

• 19

What is the mass, in grams, of 4.725 mole of aluminum oxide Al₂O₃?{Al = 27, O = 16}

• 964 g

• 482 g

• 1928 g

How many moles of iron (III) oxide are contained in 276 g of pure Fe₂O₃? {Fe = 56, O = 16}

• 0.57 moles

• 1.71 moles

• 3.42 moles

Silver nitrate (AgNO₃) is used to make several different silver halides used in photographic films. How many formula units of AgNO3 are there in 3.25 mol AgNO₃?

• 1.96 x 10²⁴

• 5.39 x 10^-24

• 1.85 x 10²³

• 5.39 x 10²³

Determine the mass in grams of each of the following.

3.57 mol Al

• 96.3 kg

• 0.13 g

• 96.3 g

• 0.13 kg