Question

1. study the dilution calculations on pages 325 - 328 of your textbook. then do the necessary calculations and explain how to make the following solutions. a complete answer requires a procedure in addition to a number.

a. 250 ml of 1.0 m hcl using 5.0 m hcl
b. 250 ml of 1.0 m h₂so₄ using 6.0 m h₂so₄

Explanation:

Step1: Use the dilution formula

The dilution formula is \(C_1V_1 = C_2V_2\), where \(C_1\) is the initial concentration, \(V_1\) is the initial volume, \(C_2\) is the final concentration, and \(V_2\) is the final volume.

For part a:
Given \(C_1 = 5.0\space M\), \(C_2=1.0\space M\), \(V_2 = 250\space mL\)
We need to find \(V_1\).
From \(C_1V_1 = C_2V_2\), we can solve for \(V_1=\frac{C_2V_2}{C_1}\)
Substitute the values: \(V_1=\frac{1.0\space M\times250\space mL}{5.0\space M}= 50\space mL\)

Procedure:

1. Use a graduated cylinder to measure out \(50\space mL\) of the \(5.0\space M\space HCl\) solution.
2. Transfer the \(50\space mL\) of \(5.0\space M\space HCl\) to a \(250\space mL\) volumetric flask.
3. Add distilled water to the volumetric flask until the volume reaches the \(250\space mL\) mark.
4. Stopper the flask and invert it several times to mix the solution thoroughly.

For part b:
Given \(C_1 = 6.0\space M\), \(C_2 = 1.0\space M\), \(V_2=250\space mL\)
Using \(V_1=\frac{C_2V_2}{C_1}\)
Substitute the values: \(V_1=\frac{1.0\space M\times250\space mL}{6.0\space M}\approx41.7\space mL\)

Procedure:

1. Use a graduated cylinder to measure out approximately \(41.7\space mL\) of the \(6.0\space M\space H_2SO_4\) solution. (Note: When handling concentrated \(H_2SO_4\), wear appropriate safety gear like gloves and goggles)
2. Transfer the \(41.7\space mL\) of \(6.0\space M\space H_2SO_4\) to a \(250\space mL\) volumetric flask.
3. Add distilled water to the volumetric flask until the volume reaches the \(250\space mL\) mark.
4. Stopper the flask and invert it several times to mix the solution thoroughly.

Answer:

a. Volume of \(5.0\space M\space HCl\) needed is \(50\space mL\). Procedure: Measure \(50\space mL\) of \(5.0\space M\space HCl\) with a graduated cylinder, transfer to a \(250\space mL\) volumetric flask, add water to the mark and mix.
b. Volume of \(6.0\space M\space H_2SO_4\) needed is approximately \(41.7\space mL\). Procedure: Measure approximately \(41.7\space mL\) of \(6.0\space M\space H_2SO_4\) (with safety precautions), transfer to a \(250\space mL\) volumetric flask, add water to the mark and mix.