4.00 mol C 8 H 18 reacts with 40.0 mol O 2 , in actual forming 917 g CO2. What is the percentage yield of such reaction?

% Yield = 81.4%

Explanation:

Based on the reaction:

C₈H₁₈ + 25/2O₂ → 8CO₂ + 9H₂O

1 mole of C₈H₁₈ reacts with 25/2 moles of O₂ to produce 8 moles of CO₂

To solve this question we must, as first, find limiting reactant. With limiting reactant we can find theoretical yield of CO₂. Percent yield is defined as:

% Yield = Actual yield (917g CO₂) / Theoretical Yield * 100

For a complete reaction of 4.00 moles of C₈H₁₈ are required:

4.00moles C₈H₁₈ * (25/2 moles O₂ / 1mol C₈H₁₈) = 50.0 moles of O₂

As there are just 40.0 moles, O₂ is limiting reactant

The theoretical yield of CO₂ from 40.0 moles of O₂ is:

40.0 moles O₂ * (8 moles CO₂ / 25/2 moles O₂) = 25.6 moles of CO₂

As molar mass of CO₂ is 44.01g/mol:

25.6 moles of CO₂ * (44.01g / mol) = 1126.7g of CO₂ is theoretical yield

And percent yield is:

% Yield = 917g / 1126.7g * 100

the law of conservation of mass states that in a chemical reaction, the total mass of reactants is equal to the total mass of products. because atoms are only rearranged in a chemical reaction, there must be the same number of sodium atoms and chlorine atoms in both the reactants and products

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.