Atom economy and percentage yield

• How can balanced equations be used to calculate theoretical masses?

  Balanced equations can be used to calculate theoretical masses by determining the mass of reactants and products involved.
• How much CaO can be produced from 34g of Ca when burnt completely in oxygen?

  80g of CaO can be produced from 34g of Ca.
• What is the first step in calculating the theoretical mass from an equation?

  The first step is to write out the equation and balance it.
• How do you calculate the number of moles of potassium from 12g?

  Moles of potassium = $\frac{12g}{39g/mol} =$$0.31 \text{ moles}$.
• What is the volume of hydrogen produced when 12g of potassium reacts with water?

  The volume of hydrogen produced is $3.84 \times 10^{-3} m^3$.
• What is the formula for calculating percentage yield?

  Percentage yield = $\frac{\text{Actual Yield}}{\text{Theoretical Yield}} \times 100$.
• What is the percentage yield if the actual yield is 32.6g and the theoretical yield is 47.6g?

  The percentage yield is 68.5%.
• What does atom economy measure?

  Atom economy measures how efficient a reaction is.
• How is atom economy calculated?

  Atom economy = $\frac{\text{Molecular mass of desired product}}{\text{Sum of molecular masses of all reactants}} \times 100$.
• Why is high atom economy important for the environment?

  High atom economy produces less waste and benefits the environment.
• What do companies aim for regarding atom economy?

  Companies aim to use reactions that tend towards 100% atom economy.
• What is the benefit of high atom economy for raw materials?

  High atom economy means raw materials are used more efficiently and is more sustainable.
• What is the advantage of having a higher atom economy regarding by-products?

  A higher atom economy means less by-products, resulting in less time and money spent separating them from the desirable product.