What is the mass of 90 average-sized apples if 2 dozen of the apples has a mass of 2.0 kg?

• 7.5 kg

• 15kg

• 30 kg

The SI unit for measuring the amount of a substance.

• Kilogram

• Mole

• Liter

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

The representative particle for copper.

• Atom

• Molecule

• Ion

The representative particle for hydrogen gas.

• Atom

• Molecule

• Ion

The representative particle for sodium ion.

• Formula unit

• Molecule

• Ion

The representative particle for magnesium chloride.

• Formula unit

• Molecule

• Ion

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