Question

Calculate the empirical formula of a compound whose molecular formula is C8H6O4 and empirical formula weight is 83.

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Answer 1

✠$\bold{Required \: answer \: :–}$

$\text{✠ Given:}$

$\begin{gathered}\boxed{\begin{array}{c} \sf \red{ • Molecular \: formula \: of \: a \: compound \: = \: C_{8} H _{6}O_{4} }\end{array}}\end{gathered}$

$\begin{gathered}\boxed{\begin{array}{c} \sf \red{ • \: Empirical \: formula \: weight \: = 83 }\end{array}}\end{gathered}$

$\text{✠ To \: find: }$

$\begin{gathered}\boxed{\begin{array}{c} \sf \red{ \: • \: Calculate \: empirical \: \: formula \: of \: a \: compound }\end{array}}\end{gathered}$

$\text{✠ Steps \: of \: finding \: molecular \: formula: }$

• Calculate the empirical formula weight of the compound from its empirical formula,

• Divide it's molecular weight by empirical weight which gives the number (n).

• Multiply the empirical formula by this number to get the molecular formula.

Molecular formula = empirical formula × n

where n = Molecular weight / Empirical formula weight.

$\text{✠ Step \: by \: step \: explaination:}$

Calculating molecular weight....

= 12 × 8 + 1 × 6 + 16 × 4

= 166

Using the given formula...

That is,

n(Empirical formula weight) = Molecular weight

Therefore, n = Molecular weight / Empirical formula weight

Now,

$= \:\dfrac{166}{83}$

$= \: 2$

empirical formula × n

As we know n is 2.

So empirical formula

$= \: C_{4} H _{6}O_{2}$

Answer 2

Answer:

Steps of finding molecular formula:

• Calculate the empirical formula weight of the compound from its empirical formula,

• Divide it's molecular weight by empirical weight which gives the number (n).

• Multiply the empirical formula by this number to get the molecular formula.

Molecular formula = empirical formula × n

where n = Molecular weight / Empirical formula weight.

\text{✠ Step \: by \: step \: explaination:}✠ Step by step explaination:

Calculating molecular weight....

= 12 × 8 + 1 × 6 + 16 × 4

= 166

Using the given formula...

That is,

n(Empirical formula weight) = Molecular weight

Therefore, n = Molecular weight / Empirical formula weight

Now,

= \:\dfrac{166}{83}=

83

166

= \: 2=2

empirical formula × n

As we know n is 2.

So empirical formula

= \: C_{4} H _{6}O_{2}=C

4

H

6

O

2