Chemical equations, the mole and molarity

Question 1

What is Avogadro’s constant

Answer 1

6.02x10^23 - standard unit
- defined as the number of atoms found in 12g of 12C
1 mole of any element contains the same number of atoms

Question 2

how to calculate molar mass

Answer 2

molar mass = mass/ moles

Question 3

what does molecular mass equal

Answer 3

molar mass

Question 4

what is the ideal gas law

Answer 4

1 mole of any gas occupies the same volume at standard temperature and pressure
PV = nRT n = number of moles R = a constant
Standard condition - T = 273 K, P = 100 kPa

Question 5

what is molarity

Answer 5

solution concentration expressed as moles of solute dissolved in one litre of solution

Question 6

how to calculate molarity

Answer 6

molarity = number of moles/volume in litres units = mol/L

Question 7

what does 1 mL = in L

Answer 7

1/1000 L

Question 8

what does 1mg = in g

Answer 8

1/1000g

Question 9

what does chemical reactions involve

Answer 9

• changes in identity of compounds
• energy changes
• breaking and making chemical bonds
• rearrangement of valence electrons

Question 10

what is the yield of a reaction

Answer 10

it is the percentage of the predicated amount that was actually made

Question 11

how to calculate % yield

Answer 11

mass in g / Ar of required compound x 100