**Chemistry Calculators** ▶ Theoretical Yield Calculator

This theoretical yield calculator is a tool for chemical reactions that calculate theoretical yield according to the theoretical yield formula. Calculating theoretical yield becomes easy with this yield calculator as it tells you how many grams of product the chemical reaction will generate.

Before performing chemical reactions, to get ease you should have to know how much product will be produced with given quantities of reactants. This is said to be as the theoretical yield. This is the phenomenon that use when calculating theoretical yield of a chemical reaction. The same phenomenon can take into account to calculate the amount of each reagent that needed to produce a desired amount of product.

Well, give a read to this article to know theoretical yield definition, theoretical yield equation, how to calculate theoretical yield along, about theoretical yield calculator, and much more!

So, let’s start with the theoretical yield definition – Read on!

In chemistry, theoretical yield is said to be the quantity of product, which obtained from the complete conversion of the limiting reactant in a chemical reaction. It is said to be the amount of product resulting from a perfect (theoretical) chemical reaction, and that’s why not as same as you will actually get from a reaction in the lab. However, theoretical yield can obtained under the perfect conditions, these conditions indicates where no product is lost in the process, means:

- no impurities mixed in the reactants
- no production of unexpected byproducts that can reduce the yield
- no loss of product because of any measurement, processing, and handling of reactants or products

Remember that theoretical yield is commonly expressed in the terms of grams or moles! You can try the above theoretical yield calculator or use the below theoretical yield formula for calculating theoretical yield!

The theoretical yield equation used in finding theoretical yield from the mole of the limiting reagent, assuming 100 percent efficiency. So, no need to worry more about how to find theoretical yield, the given theoretical yield formula does work best for you!

mass of product = molecular weight of product * (moles of limiting reagent in reaction * stoichiometry of product)

Where;

- moles of limiting reagent in reaction = mass of limiting reagent/ (molecular weight of limiting reagent * stoichiometry of limiting reagent)
- Stoichiometry is said to be as the number before the chemical formula in a balanced reaction. If no number is found, then the stoichiometry is said to be 1. Keep in mind, the stoichiometry is the thing that needed to reflect the ratios of molecules that comes together to form a product. However, the above yield calculator can be used any way you like, it not only helps to perfrom theoretical yield calculation but also calculate limiting reagent (moles), and stoichiometry of product.

The theoretical yield calculator will helps to estimate how many grams of product each reagent can produce, if fully consumed with no byproducts. This calculator helps you in calculating theoretical yield, limiting reagent (moles), and also stoichiometry of product by using theoretical yield equation.

You just have to stick to the following steps to calculate theoretical yield, read on!

**About Limiting reagent:**

- At first, you have to enter the mass of limiting reagent into the designated field of the above calculator, it can either be in µg, mg, g, kg, lbs
- Very next, you have to enter the molecular weight of limiting reagent into the designated field
- Now, you have to enter the stoichiometry of limiting reagent into the designated box

**About Desired Product:**

- Here, you have to enter the number of moles that you found from the balanced equation into the designated field
- Very next, you have to enter the molecular weight of the desired product into the designated

Once you added all the above values, simply hit the calculate button, this smart calculator for theoretical yield shows:

- Theoretical Yield
- Limiting Reagents (moles)
- Stoichiometry of Product

Finding theoretical yield becomes easy by identifying the limiting reactant of a balanced chemical reaction. In order to calculate it, the first step is to balance the equation, if it’s unbalanced.

In very next step, you have to identify the limiting reactant (this all based on the mole ratio between the reactants. Remember that the limiting reactant is not found in excess, so the reaction cannot proceed, if once it is used up!

So, to find the limiting reactant, you need to:

- If the quantity of reactants is given in moles, then you have to convert the values into grams
- Very next, you have to divide the mass of the reactant in grams by its molecular weight in grams per mole
- Alternatively, for a liquid solution, you ought to multiply the amount of reactant solution in milliliters by its density in grams per milliliter. Then, you have to divide the resulting value by the reactant’s molar mass
- Now, you ought to multiply the mass obtained using either method by the number of moles of reactant in the balanced equation
- Now you come to know the moles of each reactant. You ought to compare this to the molar ratio of the reactants to decide which is available in excess and will here used up first (the limiting reagent)
- Once you determined the limiting reactant, you ought to multiply the moles of limiting reaction times the ratio between moles of limiting reactant & product from the balanced equation. By this, you will get the number of moles of each product.

To get the grams of product, you have to multiply the moles of each product by its molecular weight.

How to calculate theoretical yield of aspirin, an experiment in which you prepare acetylsalicylic acid (aspirin) from salicylic acid, and you know from the balanced equation for aspirin synthesis in which the mole ratio between the limiting reactant (salicylic acid) and the product (acetylsalicylic acid) is 1:1.

If you have 0.00153 moles of salicylic acid, then the theoretical yield is:

Theoretical yield = 0.00153 mol salicylic acid * (1 mol acetylsalicylic acid / 1 mol salicylic acid) * (180.2 g acetylsalicylic acid / 1 mole acetylsalicylic acid)

Theoretical Yield = 0.276 grams acetylsalicylic acid (aspirin)

A limiting reagent is said to be a chemical reactant that limits the amount of product that is formed. Moreover, the limiting reagent is the thing that gives the smallest yield of product calculated from the available reagents (reactants). This smallest yield of product is said to be theoretical yield.

Let’s solve it with the theoretical yield example!

According to the given balanced chemical equation, if 4.50 g of HCl are reacted with 15.00 g of CaCO3, then calculate the theoretical yield of carbon dioxide (CO2)!

2HCl + CaCO3 → CaCl 2 + H2O + CO2

1: At the first, you have to determine the number of moles of one of the products (CO2 in this example) produced if all of each reactant is used up

4.50 g HCl x 1mol HCl / 36.5 g HCl x 1molCO2/2mol HCl = 0.0616molCO

15.00 g CaCO3 x 1molCaCO3 / 100.1g CaCO3 x 1molCO2 / 1molCaCO3 = 0.1499 molCO2

2: Now, you ought to use the smallest number of moles of the product (CO2) from step 1 to calculating the theoretical yield of product (CO2).

0.0616 molCO2 x 44.0 g CO2 / 1molCO2 = 2.71g CO2

According to the equation given below, if 112 g of nitrogen gas reacts with hydrogen gas to generate 40.8 g of ammonia gas:

N2(g) + 3H2(g) ⇋ 2NH3(g)

Calculate the percentage and theoretical yield of ammonia:

Solution:

1. Actual yield is said to be the mass of ammonia that is actually produce during the chemical reaction

Actual yield of ammonia (NH3) = 40.8 g (given in the above question)

2. Theoretical yield of ammonia (NH3) is said to be the mass of product predicted by the balanced chemical equation for the reaction.

By the balanced chemical equation the mole ratio that is stoichiometric ratio N2:NH3 is 1:2

Thus, moles NH3 = 2 × moles N2

Assuming all the available N2 reacts completely, then the maximum amount of ammonia (NH3) that can be produced is:

moles NH3 = 2 × (mass N2 ÷ molar mass N2) = 2 × (112 ÷ [2 × 14]) = 2 × (112 ÷ 28) = 8 mol

Theoretical yield NH3 = predicted mass NH3

Predicted mass NH3 = maximum mass of ammonia (NH3) that can be produced assuming that all the N2 reacts completely:

mass(NH3) = moles(NH3) × molar mass(NH3)

predicted mass NH3 = 8 × (14 + 3 × 1) = 8 × 17 = 136 g

Theoretical yield = predicted mass = 136 g

3. Percentage yield = (actual yield ÷ theoretical yield) × 100

Now, submitting the values for actual yield and theoretical yield into the above equation:

percentage yield NH3 = (40.8 ÷ 136) × 100 = 30%

The theoretical yield of Cl2 is 22.9 g

When it comes to find the theoretical yield, stick to the given steps:

- You have to balance your equations
- You ought to find the mole ratio between the reactant and the product
- Calculate it by using the above theoretical yield calculator and strategy

Hope so, the above stuff about calculation of theoretical yield works best for you!

From a chem.libretexts – All about chemistry – Excess reagent, limiting reagent – Theoretical Yield – calculate theoretical yield

The source of oneclass offers ultimate solutions of Chemistry – how to calculate theoretical yield of aspirin

By GCSEOCR 21st Century – Calculating yields – OCR 21C – Calculate the maximum theoretical yield – Chemical Reaction Analysis