Respuesta :
To determine te volume of the solution given the amount of solute present, we simply divide the amount in moles with the concentration in molarity. First, we make sure the amount of solute is expressed in moles.
moles KCl = 2.55 g KCl / 74.55 g/mol = 0.0342 mol KCl
Volume of solution = 0.0342 mol / 0.155 mol /L = 0.221 L solution or 221 mL of the solution
moles KCl = 2.55 g KCl / 74.55 g/mol = 0.0342 mol KCl
Volume of solution = 0.0342 mol / 0.155 mol /L = 0.221 L solution or 221 mL of the solution
[tex]\boxed{{\text{0}}{\text{.221 L}}}[/tex] of a 0.155 M KCl solution contains 2.55 g of KCl.
Further Explanation:
The proportion of substance in the mixture is called concentration. The most commonly used concentration terms are as follows:
1. Molarity (M)
2. Molality (m)
3. Mole fraction (X)
4. Parts per million (ppm)
5. Mass percent ((w/w) %)
6. Volume percent ((v/v) %)
Molarity is a concentration term that is defined as the number of moles of solute dissolved in one litre of the solution. It is denoted by M and its unit is mol/L.
The formula to calculate the molarity of the KCl solution is as follows:
[tex]{\text{Molarity of KCl solution}}=\frac{{{\text{Moles}}\;{\text{of}}\;{\text{KCl}}}}{{{\text{Volume }}\left( {\text{L}} \right){\text{ of}}\;{\text{KCl solution}}}}[/tex] …… (1)
Rearrange equation (1) to calculate the volume of the KCl solution.
[tex]{\text{Volume of}}\;{\text{KCl solution}}=\frac{{{\text{Moles}}\;{\text{of}}\;{\text{KCl}}}}{{{\text{Molarity of KCl solution}}}}[/tex] …… (2)
The formula to calculate the moles of KCl is as follows:
[tex]{\text{Moles of KCl}}=\frac{{{\text{Given mass of KCl}}}}{{{\text{Molar mass of KCl}}}}[/tex] …… (3)
The given mass of KCl is 2.55 g.
The molar mass of KCl is 74.55 g/mol.
Substitute these values in equation (3).
[tex]\begin{aligned}{\text{Moles of KCl}}&=\left({{\text{2}}{\text{.55 g}}}\right)\left( {\frac{{{\text{1 mol}}}}{{{\text{74}}{\text{.55 g}}}}}\right)\\&=0.03420\;{\text{mol}} \\ \end{aligned}[/tex]
Substitute 0.03420 for the moles of KCl and 0.155 M for the molarity of KCl solution in equation (2).
[tex]\begin{aligned}{\text{Volume of KCl solution}}&=\left( {{\text{0}}{\text{.03420 mol}}} \right)\left( {\frac{{{\text{1 L}}}}{{{\text{0}}{\text{.155 mol}}}}} \right) \\&={\text{0}}{\text{.2206 L}}\\&\approx {\text{0}}{\text{.221 L}}\\\end{aligned}[/tex]
The volume of the KCl solution is 0.221 L.
Learn more:
1. Calculation of volume of gas: https://brainly.com/question/3636135
2. Determine how many moles of water produce: https://brainly.com/question/1405182
Answer details:
Grade: Senior School
Subject: Chemistry
Chapter: Concentration terms
Keywords: molarity of KCl solution, 0.221 L, volume of KCl solution, moles of KCl, given mass, molar mass, 74.55 g/mol, 2.55 g, 0.155 M.
