Solving Stoichiometry

By: Alyson Nea

Assigned Reaction

Aluminum and Silver Sulfate.

Type of Reaction

Single Replacement. It's when a type of oxidation-reduction chemical react to an element or ion that moves out of one compound and into another.

A + BX -----> B + AX

Element A has replaced B (in the compound BX) to form a new compound AX and the free element B.

Blanced Equation

_Al + _Ag_(SO4)2 ------> _Ag + Al_(SO4)2

2Al + 3Ag2(SO4) ------> 6Ag + Al2(SO4)3

To Balance an Equation, both side must have the same Mass, But there are Coefficients that need to be moved. Since Al has switched places with Ag. The Coefficients between Al and (SO4)2 Must be changed. Al has 3 moles and it's mole has to switch with the Sulfate. Then, Al_(SO4)2 turns into Al2(SO4)3.

Now there are 2 Al's on the left side, and we have to balance the Al by multiplying 2 on the other side of the Equation. So, we place a 2 next to the Al. There's also 3 (SO4)2 on the left side of the Equation, so we have to put a 3 next to Ag to Balance out the Equation. Then there's 3Ag on the right, and since it's 3Ag2, it's multiplied by 2. 3 times 2 is 6, so we put 6 next to Ag on the left side of the Equation.

IUPAC Name

Aluminum + Silver Sulfate ------> Silver + Aluminum Sulfate

Because it's a Single Replacement, and Aluminum replaced Silver.

Molar Mass for Each Reactant and Product

Al + Ag(SO4)2 ----> Ag + Al(SO4)2

- Al = 26.982 g/Mole

- Ag = 107.87 g/Mole

- Ag(SO4)2 = 299.982 g/Mole

- Al(SO4)2 = 342.132 g/Mole

Mole to Mole Conversions

8.24| 1 mole Al(SO4)2 Multiplied together and then divided by |2 Mole Al to get 4.12 Mole Al(SO4)2 .

We add 1 Mole because it's the Coefficient from the Balanced Equation from Earlier. We Multiply it by 8.24 because It asks for my Birthday. Then, we Divided by 2Mole Al because it's also from the Coefficient from the Balanced Equation. After Multiplying and Dividing, We get 4.12 Mole of Al(S04)2.

Mass to Mass Conversions

12.1gAl X 1 Mole X 3 Mole Ag(SO4)2 X 299.992 = 10889.7096

10889.7096 Divided by 26.982 X 2 = 67.265g/Ag(So4)2

We started with 12.1 because it was the date. Then we Multiplied by 1 Mole because it's on top of a mass, and the mole is Always 1 if it's at the beginning. Then we Multiply by 3 Mole Ag(SO4)2 because it's the Coefficient from the Earlier Equation, then we multiply by 2999.992 because it's the Molar Mass of Ag(SO4)2. Then we get 10889.7069.

Afterwards we Divide by 26.982 because it's the Molar mass of Aluminum, then Multiply it by 2 because it's the Coefficient from the Earlier Equation.

Limiting And Excess Reactant

12.3g Al x 1 Mole Al X 6 Mole Ag X 107.868 g Ag X = 1174356.327

1174356.357 divided by 26.982 X 2 = 147.52g Ag

Limiting = Ag(SO4)2

Excess = Al

We started with 12.3 because it was the Date, then Multiply 1 mole because it's on top of a mass, and if a Mole Is on top of a mass, it's automatically 1. Then we multiply by 6 Mole Ag because It's from the Coefficient from the Earlier Equation. (6Ag + Al2(SO4)3). Then we multiply by 107.868g because it's the Molar Mass of Ag. Then we get 1174356.327, and we divide that with 26.982 because it's the Molar Mass of Aluminum. Then we Multiply by 2 because it's the Coefficient from the Equation. and we get 147.52g Ag. Our Limiting Element is Ag(SO4)2 and our Excess Element is Al.

Theoretical Yield

12.3 Ag (So4)2 X 1 Mole x 6 Mole g Ag X 107.87 = 7960.806

7960.806 Divided by 299.82 g/Mole X 3mole x 1 Mole Ag =8.85g

We started with 12.3 because it was the date. We multiply it by 1 Mole because it's on top of a mass and it'd always start with 1. Then we Multiply with 6 mole Ag because it's a Coefficient. Then we Multiply by 107.87 because it's the Molar Mass of Ag. Then we get 7960.806. Then we divided by 299.82g Mole because it's the Molar Mass of Ag(SO4)2 and Multiply by 3 mole because it's a Coefficient and then we Multiply it by 1 mole Ag. And then our answer is 8.85g, which is Theoretical.

Precent Yield

Actual Yield 6.99g Ag

So we put 8.85g to divide by 6.99 and then Multiply by 100 to get 126.60g/Mole

Proof Of Reaction

The reaction between silver sulfide and aluminum takes place when the two are in contact while they are immersed in a baking soda solution. The reaction is faster when the solution is warm. The solution carries the sulfur from the silver to the aluminum.