# Chemistry

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When 4.0 mol of CCl4 reacts with an excess of HF, 3.0 mol of CCl2F2 (Freon) is obtained. The equation for the reaction is

CCl4(l) + 2HF(g) --> CCl2F2(l) + 2HCl9g)

State which of the statements are true about the reaction and make the false statements true.
(a) The theoretical yield for CCl2F2 is 3.0 mol.
(b) The theoretical yield for HCl is 71 g.
(c) The percent yield for the reaction is 75%.
(d) The theoretical yield cannot be determined unless the exact amount of HF is given.
(e) From just the information given above, it is impossible to calculate how much HF is unreacted.
(f) For this reaction, as well as for any other reaction, the total number of moles of reactants is equal to the total number of moles of product.
(g) Half a mole of HF is consumed for every mole of CCl4 used.
(h) At the end of the reaction, no CCl4 is theoretically left unreacted.

I'm kind of confused on how to figure out the theoretical yield and percent yield using the information.

• Chemistry - ,

c is correct.
1 mole CCl4 produces 1 mole Freon. So 4 moles CCl4 should produce 4.0 moles Freon. 4.0 moles Freon is the theoretical yield. The problem states that 3.0 moles Freon were produced; therefore, the %yield = (3.0/4.0)*100 = 75%.

c is not the only true statement in the list.

• Chemistry - ,

Okay thank you!

• Chemistry - ,

What is the density of Freon-11 (CFCl3) at 120°C and 1.5 atm?