The Mole Flashcards
Quantitative Chemistry (13 cards)
What is the Avogadro constant represented as?
6.02 x 10^23
Avogadro’s constant is the number of particles in one mole of a substance.
How many particles are in one mole of any substance?
6.02 x 10^23
Particles can be atoms, molecules, ions, or electrons.
What is the relationship between the mass of a mole of substance and its relative atomic or formula mass?
The mass in grams is equal to the relative atomic mass (A) or relative formula mass (M)
This holds true for any substance.
What is the mass of one mole of carbon?
12 g
Carbon has a relative atomic mass (A) of 12.
What is the mass of one mole of nitrogen gas (N2)?
28 g
Nitrogen gas has a relative formula mass (M) of 28 (2 x 14).
What is the mass of one mole of carbon dioxide (CO2)?
44 g
Carbon dioxide has a relative formula mass (M) of 44 (12 + [2 x 16]).
What does 12 g of carbon, 28 g of N2, and 44 g of CO2 all contain?
One mole or 6.02 x 10^23 particles
This is the same number of particles for each substance.
What is the formula to find the number of moles in a given mass?
Number of moles = mass in g / Mr
Mr is the relative mass of the element or compound.
How do you calculate the Mr of carbon dioxide (CO2)?
Mr of CO2 = 12 + (16 x 2) = 44
This is the sum of the atomic masses of carbon and oxygen.
How many moles are there in 66 g of carbon dioxide (CO2)?
1.5 mol
Using the formula: Number of moles = 66 g / 44 g/mol.
What mass of carbon is present in 4 moles of carbon dioxide?
48 g
There are 4 moles of carbon in 4 moles of CO2 (4 x 12 g/mol).
Fill in the blank: One mole of atoms or molecules has a mass in grams equal to the _______.
relative formula mass (A or M)
This applies to any substance.
True or False: The number of moles can be calculated by rearranging the formula triangle.
True
You can find mass or Mr from known values.
