Part A How many gold atoms are there in a 4.65-g sample of pure gold, Au (197 am
ID: 961494 • Letter: P
Question
Part A
How many gold atoms are there in a 4.65-g sample of pure gold, Au (197 amu)?
N=
Part B
How many grams of water, H2O, can be formed from the reaction of 6.4 g of 2-propanol, C3H8O?
C3H8OC3H6+H2O
Express your answer to two significant figures and include the appropriate units.
Part C
How many grams of propene, C3H6, can be formed from the reaction?
Express your answer to two significant figures and include the appropriate units.
Part D
Upon ignition, what is the maximum mass of carbon dioxide, CO2, that can be formed?
CH4+2O2CO2+2H2O
Express your answer to two significant figures and include the appropriate units.
Explanation / Answer
4.65 g of Au
mol = mass/MW = 4.65/197 = 0.0236 mol
1 mol = 6.022*10^23
atoms = 0.023*6.022*10^23 = 1.385*10^22 atoms of gold
B)
mol of propanol = mass/MW = 6.4/60.09502 = 0.106498 mol
then
ratio is 1:1 then 0.106498 mol of H2O forms
mass = mol*MW = 0.106498*18 = 1.916964 g of H2O
C)
same amount of moles; that is 0.106498 mol of propene
mass = mol*MW = 42.08*0.106498 = 4.48143 g of propene
D)
impossible to determine with no mass