IDNLearn.com makes it easy to find accurate answers to your questions. Our platform is designed to provide reliable and thorough answers to all your questions, no matter the topic.

What is the molarity of a solution that contains 25 g of HCl in 150 mL of solution? (The molar mass of HCl is [tex]36.46 \, g / mol[/tex].)

1. What should you find first?

2. Which setup is correct for finding moles?
A. [tex]25 \, g \, HCl \times \frac{36.46 \, g \, HCl}{1 \, mol \, HCl}[/tex]
B. [tex]25 \, g \, HCl \times \frac{1 \, mol \, HCl}{36.46 \, g \, HCl}[/tex]

3. Which setup is correct to find liters?
A. [tex]150 \, mL \times \frac{1000 \, mL}{1 \, L}[/tex]
B. [tex]150 \, mL \times \frac{1 \, L}{1000 \, mL}[/tex]

4. What is the molarity of this solution?
A. 4.5 M HCl


Sagot :

To determine the molarity of a solution containing 25 grams of HCl in 150 mL of solution, we need to follow a series of steps. Here's a detailed, step-by-step solution:

1. Find the number of moles of HCl:
- The formula used to convert grams to moles is:
[tex]\[ \text{moles of HCl} = \frac{\text{mass of HCl (in grams)}}{\text{molar mass of HCl (in g/mol)}} \][/tex]
- Given:
[tex]\[ \text{mass of HCl} = 25 \text{ grams} \][/tex]
[tex]\[ \text{molar mass of HCl} = 36.46 \text{ g/mol} \][/tex]
- Therefore, the number of moles of HCl is:
[tex]\[ \text{moles of HCl} = \frac{25 \text{ g}}{36.46 \text{ g/mol}} \approx 0.6857 \text{ moles} \][/tex]
- The correct setup to find the moles of HCl is:
[tex]\[ 25 \text{ g HCl} \times \frac{1 \text{ mol HCl}}{36.46 \text{ g HCl}} \][/tex]

2. Convert the volume of solution from mL to L:
- The formula to convert milliliters to liters is:
[tex]\[ \text{volume in liters} = \frac{\text{volume in mL}}{1000} \][/tex]
- Given:
[tex]\[ \text{volume of solution} = 150 \text{ mL} \][/tex]
- Therefore, the volume in liters is:
[tex]\[ \text{volume in liters} = \frac{150 \text{ mL}}{1000} = 0.15 \text{ L} \][/tex]
- The correct setup to convert volume is:
[tex]\[ 150 \text{ mL} \times \frac{1 \text{ L}}{1000 \text{ mL}} \][/tex]

3. Calculate the molarity of the solution:
- Molarity is defined as the number of moles of solute per liter of solution:
[tex]\[ \text{Molarity (M)} = \frac{\text{moles of solute}}{\text{volume of solution in liters}} \][/tex]
- Given:
[tex]\[ \text{moles of HCl} \approx 0.6857 \text{ moles} \][/tex]
[tex]\[ \text{volume of solution} = 0.15 \text{ L} \][/tex]
- Therefore, the molarity of the solution is:
[tex]\[ \text{Molarity} = \frac{0.6857 \text{ moles}}{0.15 \text{ L}} \approx 4.57 \text{ M} \][/tex]

The molarity of the solution is approximately [tex]\(4.57 \text{ M}\)[/tex].