Question

Calculate the mass percentage of benzene ( \[{{C}_{6}}{{H}_{6}}\]) and carbon tetrachloride (\[CC{{l}_{4}}\]) if 22 g of benzene is dissolved in 122 g of carbon tetrachloride.

Answer 1

Hint: We should know about calculating mass percentage. We should know that we use mass percentage to represent the concentration of an element in a compound or a component in a mixture. We calculate mass percentage by the mass of a component divided by the total mass of the mixture, multiplied by 100%.

Complete step by step solution:
To solve this question, we should know about mass percentage. We use mass percentage to calculate concentration of a compound in a given mixture. We calculate mass percentage by mass of component divided by total mass of mixture multiplied by 100%. We will use this concept in calculating the mass percentage of benzene and carbon tetrachloride in a mixture of both of them.
In the above question, it is already given that 22 gram of benzene is dissolved in 122 gram of carbon tetrachloride.
Total weight of mixture will:
$=(given\,weight\,of\,benzene+\,given\,weight\,of\,carbon\,\,tetrachloride)$
So, total weight of mixture will be=
$\begin{align}
& =22gram\,benzene+\,122\,gram\,carbon\,\,tetrachloride \\
& =144\,gram \\
\end{align}$
Formula to calculate mass percentage of given compound:
$\begin{align}
& Mass\,\%\,of\,benzene=\dfrac{given\,weight\,of\,benzene}{weight\,of\,mixture}\times 100\% \\
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\end{align}$
So, now putting the values:
$\begin{align}
& Mass\,\%\,of\,benzene=\dfrac{122gram}{144\,gram}\times 100\%\to 84.72\% \\
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\end{align}$
In the same way we will calculate mass % carbon tetrachloride.
$\begin{align}
& Mass\,\%\,of\,CC{{l}_{4}}=\dfrac{122gram}{144\,gram}\times 100\%\to 84.72\% \\
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\end{align}$$\begin{align}
& Mass\,\%\,of\,CC{{l}_{4}}=\dfrac{122gram}{144\,gram}\times 100\%\to 84.72\% \\
& \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\end{align}$

So, from the above calculation we find out the mass % of benzene and carbon tetrachloride.
Mass % of benzene in a mixture of benzene and carbon tetrachloride is 15.27%.
Mass % of carbon tetrachloride in mixture of benzene and carbon tetrachloride is 84.72%

Note:We should know about other concentration measuring terms that are used in chemistry. Such as:
- Volume Percent: The volume percent is used to express the concentration of a solution when the volume of a solute and the volume of a solution are given.
Sometimes we notice that solutions are too dilute, their percentage concentrations are too low. So, instead of using really low percentage concentrations such as 0.00001% or 0.000000001%, we choose another way to express the concentrations. We use parts per million to describe dilute concentrations.