Answer :
Answer:
Explanation:
To calculate the concentration of a potassium chloride (KCl) solution in percentage mass by mass (% w/w) given its percentage mass by volume (% m/v) and density, we can follow these steps:
1. **Given Data:**
- The solution is 35% mass by volume (% m/v).
- The density of the solution is 1.2 g/mL.
2. **Definitions:**
- % m/v means grams of solute per 100 mL of solution.
- % w/w means grams of solute per 100 grams of solution.
3. **Calculate the Mass of the Solution:**
- Since the density is 1.2 g/mL, 100 mL of the solution will have a mass of:
\[
\text{Mass of solution} = \text{Volume} \times \text{Density} = 100 \, \text{mL} \times 1.2 \, \frac{\text{g}}{\text{mL}} = 120 \, \text{g}
\]
4. **Calculate the Mass of KCl:**
- 35% m/v means 35 grams of KCl per 100 mL of solution.
5. **Calculate the Mass of Water:**
- The mass of the solution is the mass of KCl plus the mass of water.
- The mass of the solution is 120 g, and the mass of KCl is 35 g, so the mass of water is:
\[
\text{Mass of water} = \text{Mass of solution} - \text{Mass of KCl} = 120 \, \text{g} - 35 \, \text{g} = 85 \, \text{g}
\]
6. **Calculate % w/w:**
- The percentage mass by mass is given by the mass of solute divided by the total mass of the solution, multiplied by 100.
\[
\% \text{w/w} = \left( \frac{\text{Mass of KCl}}{\text{Mass of solution}} \right) \times 100 = \left( \frac{35 \, \text{g}}{120 \, \text{g}} \right) \times 100
\]
\[
\% \text{w/w} = \left( \frac{35}{120} \right) \times 100 \approx 29.17\%
\]
Therefore, the concentration of the KCl solution in percentage mass by mass (% w/w) is approximately **29.17%**.
Answer:
29.167%
Explanation:
Step-1:
Calculate the mass of the given solution.
It is given that solution of Potassium chloride
has a concentration of 35% (m/v) .
- (m/v) represents mass by volume. It is a way to represent the concentration of the solution.
- It is defined as the mass of the solute in g dissolved in per 100 ml of the solution.
- 35% (m/v) can be interpreted as 35g of Potassium chloride (solute) is present in 100 ml of the solution according to the formula given below:
A solution comprises two parts i.e.; solute and solvent
- Solute: The component of the solution to be dissolved or the component present in the solution in a lesser quantity.
- Solvent: The component of the solution that dissolves or the component present in the solution in a larger quantity.
[tex]concentration \: in \: ( \frac{m}{v} ) \:\% \: = [/tex]
[tex] \frac{mass \: of \: the \: solute \: (g)}{volume \: of \: the \: solution \: (ml)} \times 100 [/tex]
……(i)
- To calculate the concentration in % (m/m) , the mass of the solution needs to be calculated first which can be done using the density of the solution.
Density of the solution =
[tex] \frac{mass \: of \: the \: solution \: (g)}{volume \: of \: the \: solution \: (ml)} [/tex]
……..(ii)
- Given, Density= 1.2 g/ml
The volume of the solution= 100 ml ....interpreted from (m/v).
Substituting the values in the formula (ii)
[tex]1.2 = \frac{mass \: of \: the \: solution}{100} [/tex]
[tex]mass \: of \: the \: solution \: = 1.2 \times 100 = 120g[/tex]
Step-2:
Calculate the concentration of the solution in %(m/m).
The formula used to calculate the concentration in %(m/m) is given below:
[tex]concentration \: in \: ( \frac{m}{m} )\% = [/tex]
[tex] \frac{mass \: of \: the \: solute \: (g)}{mass \: of \: the \: solution \: (g)} \times 100[/tex]
- (m/m) represents mass by mass. It is a way to represent the concentration of the solution.
- It is defined as the mass of the solute in dissolved in per 100gof the solution.
Mass of the solute= 35g (interpreted above)
Mass of the solution= 120g (calculated above)
[tex]conc. \: in \: \frac{m}{m}\%= \frac{35}{120} \times 100 [/tex]
[tex] \frac{3500}{120} = 29.167\%[/tex]
Hope it helps :)