Question

Be + 2 HCl ➞ BeCl2 + H2

Calculate the percent yield if 25.0 g of beryllium reacts with excess HCl to produce 190.g BeCl2.

Answer 1

The percent yield of BeCl2 when 25.0 g of beryllium reacts with excess HCl to produce 190.0 g BeCl2, is calculated by dividing the actual yield by the theoretical yield and then multiplying by 100, resulting in a percent yield of 85.6%.

Step-by-step explanation:

To calculate the percent yield of the reaction that produces BeCl2 from beryllium (Be) and hydrochloric acid (HCl), we first need to find the theoretical yield of BeCl2 and then use the actual yield to calculate the percent yield. The balanced chemical equation for the reaction is:

Be + 2 HCl → BeCl2 + H2

The molar mass of Be is approximately 9.012 g/mol, and the molar mass of BeCl2 is approximately 80.0 g/mol. Using stoichiometry, we can find the theoretical yield of BeCl2:

1. Calculate moles of Be: (25.0 g Be) / (9.012 g/mol) = 2.774 moles Be.
2. Since Be reacts with HCl in a 1:1 molar ratio to produce BeCl2, we also have 2.774 moles of BeCl2 as the theoretical yield.
3. Convert moles of BeCl2 to grams: 2.774 moles BeCl2 * 80.0 g/mol = 221.9 g (theoretical yield).
4. Calculate the percent yield: (190.0 g actual yield) / (221.9 g theoretical yield) * 100 = 85.6% percent yield.

Therefore, the percent yield of the reaction producing BeCl2 is 85.6%.

Answer 2

Step-by-step explanation:

The balanced chemical equation for the reaction between beryllium and hydrochloric acid is:

Be + 2 HCl → BeCl2 + H2

From the equation, we can see that 1 mole of beryllium reacts with 2 moles of hydrochloric acid to produce 1 mole of beryllium chloride and 1 mole of hydrogen gas. The molar mass of Be is 9.01 g/mol, and the molar mass of BeCl2 is 79.92 g/mol.

First, we need to calculate the theoretical yield of BeCl2:

Calculate the number of moles of Be in 25.0 g:

25.0 g / 9.01 g/mol = 2.77 mol Be

Calculate the number of moles of BeCl2 that can be produced, based on the balanced equation:

2.77 mol Be × (1 mol BeCl2 / 1 mol Be) = 2.77 mol BeCl2

Calculate the mass of BeCl2 that can be produced:

2.77 mol BeCl2 × 79.92 g/mol = 221.7 g BeCl2

Therefore, the theoretical yield of BeCl2 is 221.7 g.

The percent yield can now be calculated using the actual yield (190 g) and the theoretical yield (221.7 g):

Percent yield = (actual yield / theoretical yield) × 100%

Percent yield = (190 g / 221.7 g) × 100%

Percent yield = 85.7%

Therefore, the percent yield of the reaction is 85.7%.