Define the Avogadro constant .

The Avogadro constant ( N A ) is 6.02 x 10 23 mol -1 . It is the number of particles (atoms, molecules, ions or electrons) in one mole of a substance.

True or False? One mole of any element has a mass equal to its relative atomic mass in grams.

True. For example, one mole of sodium (A r = 23.0) has a mass of 23.0 g, and one mole of carbon (A r = 12.0) has a mass of 12.0 g.

How many molecules are in 1 mole of H 2 , and how many individual H atoms does this correspond to?

1 mole of H 2 contains 6.02 × 10 23 molecules. Since each molecule has 2 H atoms, this corresponds to 2 × 6.02 × 10 23 = 1.204 × 10 24 H atoms.

The Avogadro constant is .......... mol -1 . A substance containing this many particles has a mass called one .......... .

The Avogadro constant is 6.02 x 10 23 mol -1 . A substance containing this many particles has a mass called one mole .

A mole is the amount of substance that contains the same number of fundamental units as there are atoms in exactly 12.00 g of carbon-12. This number is 6.02 x 10 23 .

What is the mass of 1 mole of NaCl? (A r : Na = 23.0, Cl = 35.5)

Mass = 23.0 + 35.5 = 58.5 g mol -1 . The molar mass is found by summing the relative atomic masses of all atoms in the formula unit.

True or False? The Avogadro constant applies only to atoms and molecules, not to ions or electrons.

False. The Avogadro constant applies to atoms, molecules, ions and electrons.

One mole of water (H 2 O) has a mass of .......... g, because the relative atomic masses of hydrogen and oxygen are .......... and .......... respectively.

One mole of water (H 2 O) has a mass of 18 g, because the relative atomic masses of hydrogen and oxygen are 1.0 and 16.0 respectively.

How many total atoms are in 1 mole of NaCl?

1 mole of NaCl contains 1.204 × 10 24 atoms in total, because each formula unit has one Na atom and one Cl atom, giving 2 × 6.02 × 10 23 atoms.

A LevelChemistryCambridge (CIE)Flashcards2. Atoms, Molecules & StoichiometryThe Mole & the Avogadro Constant

The Mole & the Avogadro Constant (Cambridge (CIE) A Level Chemistry): Flashcards

Exam code: 9701

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FrontThe Mole & the Avogadro Constant
Define the Avogadro constant.

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Cards in this collection (9)

Define the Avogadro constant.
The Avogadro constant (N_A) is 6.02 x 10²³ mol^-1. It is the number of particles (atoms, molecules, ions or electrons) in one mole of a substance.
True or False?
One mole of any element has a mass equal to its relative atomic mass in grams.
True.
For example, one mole of sodium (A_r = 23.0) has a mass of 23.0 g, and one mole of carbon (A_r = 12.0) has a mass of 12.0 g.
How many molecules are in 1 mole of H₂, and how many individual H atoms does this correspond to?
1 mole of H₂ contains 6.02 × 10²³ molecules. Since each molecule has 2 H atoms, this corresponds to 2 × 6.02 × 10²³ = 1.204 × 10²⁴ H atoms.
The Avogadro constant is .......... mol^-1. A substance containing this many particles has a mass called one .......... .
The Avogadro constant is 6.02 x 10²³ mol^-1. A substance containing this many particles has a mass called one mole.
Define mole.
A mole is the amount of substance that contains the same number of fundamental units as there are atoms in exactly 12.00 g of carbon-12. This number is 6.02 x 10²³.
What is the mass of 1 mole of NaCl? (A_r: Na = 23.0, Cl = 35.5)
Mass = 23.0 + 35.5 = 58.5 g mol^-1. The molar mass is found by summing the relative atomic masses of all atoms in the formula unit.
True or False?
The Avogadro constant applies only to atoms and molecules, not to ions or electrons.
False.
The Avogadro constant applies to atoms, molecules, ions and electrons.
One mole of water (H₂O) has a mass of .......... g, because the relative atomic masses of hydrogen and oxygen are .......... and .......... respectively.
One mole of water (H₂O) has a mass of 18 g, because the relative atomic masses of hydrogen and oxygen are 1.0 and 16.0 respectively.
How many total atoms are in 1 mole of NaCl?
1 mole of NaCl contains 1.204 × 10²⁴ atoms in total, because each formula unit has one Na atom and one Cl atom, giving 2 × 6.02 × 10²³ atoms.

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