Limiting Reactants and ICE Charts

Download Report

Transcript Limiting Reactants and ICE Charts

Limiting Reactants and ICE Charts

Chemistry Cake

You have

20 cups

of flour,

8 cups

of sugar,

30 litres

of milk and

48 eggs

in your kitchen. The recipe for chemistry cake is:

+ 3 cups of flour 2 cups of sugar 2 litres of milk 6 eggs = 1 chemistry cake

1.

How many cakes can you make?

2.

Which ingredient ran out first and limited the number of cakes you could make?

3.

What and how much of each ingredient is left over?

4.

What does this assignment have to do with chemistry?

I nitial C hange 12 E nd 3 20 8 F + 2 S + 8 8 0 2 M 30 8 22 + 6 E → 1 Cake 48 24 24

The sugar runs out-

limiting ingredient 8 cups

of sugar will make

4 cakes

- so multiple the

recipe by 4

All other ingredients are in excess

0 4 4

Limiting Reactant Problems

14.0 mole Ga and 12.0 mole O 2 react. Find the limiting reactant, the mass of excess reactant and product made.

4 Ga + 3 O 2 → Ga 2 O 3

I

14.0

12.0

0

4

C

16.0

12.0

3 Guess

that one of the reactants runs out- then

check

Cannot consume

16.0 moles

– we only have

14 moles

14.0 mole Ga and 12.0 mole O 2 react. Find the limiting reactant, the mass of excess reactant and product made.

4 Ga + 3 O 2 → Ga 2 O 3

I

14.0

12.0

0

3 2

C

14.0

10.5

7.00

E

0

4

1.5

3

x 32.0 g 1 mole 7.00

x 187.4 g 1 mole

48. g 1.31 x 10 3 g

limiting excess product

The other reactant must

run out-

calculate the

change Subtract

to get what is left- Convert back to

grams

14.0 g of Al reacts with 94.0 g of Br 2 . Find the limiting reactant, the mass of the excess reactant and product.

I C

2

Al + 14.0 g x 1 mole 27.0 g 0.5185 mole 0.5185 mole

3 2 3

Br 2 94.0 g x 1 mole 159.8 g → AlBr 3 0.5882 mole 0.7778 mole 0 mole

I C E 14.0 g of Al reacts with 94.0 g of Br 2 . Find the limiting reactant, the mass of the excess reactant and product.

2

Al + 14.0 g x 1 mole 27.0 g 0.5185 mole

2

0.3921 mole 0.1264 mole

3

x 27.0 g 1 mole

3.41 g 3

Br 2 94.0 g x 1 mole 159.8 g → AlBr 3 0.5882 mole 0.5882 mole 0.0000

limiting 2 3

0 mole 0.3921 mole 0.3921 mole x 266.7 g 1 mole

105 g

25.0 g of H 3 PO 4

reacts with

94.0 g of Ca(NO 3 ) 2

. Find the limiting reactant, the mass of the excess reactant and product.

2

H 3 PO 4 + Ca(NO 3 ) 2 →

1

Ca 3 (PO 4 ) 2 +

25.0 g x 1 mole 98.03 g 94.0 g x 1 mole 164.1 g 6

HNO 3 I 0.2550 mole C 0.2550 mole E 0 mole

3 2

0.5728 mole 0.3825 mole 0.1903 mole

1 3

0 mole 0.1275 mole

6 1

0.1275 mole 0 mole 0.765 mole 0.765 mole

x 164.1 g x 310.3 g x 63.01 g 1 mole 1 mole 1 mole limiting = 31.2 g = 39.6 g = 48.2 g