In: Chemistry
1) Find the mass (in g) of F in 0.0480 g of CFCl3?
2) A hydrocarbon contains 18.3% H and 81.7% carbon. Find the empirical formula of the compound?
3) How many moles in 24.02g of Co?
4) How many grams in 8.79 moles of CH4?
5) What is the empirical formula of a compound containing C, H, and O if combustion of 3.69 g of the compound yields 5.40 g of CO2 and 2.22 g of H2O?
1) 1 mole of CFCl3 contains 1 mole of F
137 g of CFCl3 contains 19 g of F
0.048 g of CFCl3 contains (19 / 137) * 0.048
= 0.006656 g of F
2) C atoms = 81.7 /12 = 6.808
H atoms = 18.3 /1 = 18.3
Smallest value = number of C = 6.808 / 6.808 = 1 atom
number of H = 18.3 / 6.808 = 2.688
to get whole number multiply with small integer = 3(1) = 3 C atoms
3(2.688) = nearly equal to 8
empirical formula = C3H8
3) 1 mole of Co is 56 g
24.02 g of Co is (24.02 / 56) = 0.4289 moles
4) 1 mole of CH4 is 16 g
8.74 moles of CH4 is (16*8.74) = 139.84 g