# Chemistry

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DDT, an insecticide harmful to fish, birds, and humans, is produced by the following reaction:

2 C 6 H 5 Cl (Chlorobenzene) + C 2 H O Cl 3(chloral) ==> C 14 H 9 Cl 5 (DDT) + H 2 O

In a government lab, 1142 g of chlorobenzene is reacted with 485g of Chloral.

A)What mass of DDT is formed?
B)Which reactant is limitin? Which is in excess?
C)What mass of the excess reactant is left over?
D)If the actual yield of DDT is 200.0 g, what is the percent yield?

Please be specific (in showing work), and show significant figures! Thank you!

• Chemistry - ,

You have the equation. Make sure it is balanced.

Convert g chlorobenzene to moles. moles = grams/molar mass.
Convert g chloral to moles.

Using the coefficients in the balanced equation, convert moles chlorobenzene to moles DDT.
Same procedure, convert moles chloral to moles DDT.
More than likely, the numbers for moles DDT will not be the same which means one of them is wrong. In limiting reagent problems, the correct value is ALWAYS the smaller one and the reactant providing that number is the limiting reagent.

Now convert the smaller value to grams. g = mols x molar mass.