The atomic number of gold (Au) is 79, and it has a mass number of 197. How many electrons are present in each atom of gold?
1 answer:
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Answer:
Option C, (Actual yield ÷ percent yield) × 100
Explanation:
Theoretical yield is defined as the total amount of product formed for given reactants in a chemical reaction. It is an ideal case which assumes no exceptions or wastage.
The mathematical relation between the actual yield, percent yield and theoretical yield is as follows -
Where
P.Y. represents the percent yield a
M A.Y. represents the mass obtained from actual yield
M T.Y. represents the mass obtained from theoretical yield
Hence, if we rearrange the formula, we get -
Hence, option C is correct
Answer: -227 kJ
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
where,
n = number of moles
(as heat of formation of substances in their standard state is zero
Now put all the given values in this expression, we get
Therefore, the enthalpy change for is -227 kJ.