How many moles of HNO3 are required to make 250mL of a 2.4M solution?

How many grams of KOH are required to make 125mL of a .50M solution?

To calculate the number of moles of HNO3 required to make a 2.4M solution in 250mL, you can use the formula:

Moles = Concentration (M) x Volume (L)

First, convert the volume from milliliters to liters:

250 mL = 250/1000 = 0.25 L

Then, substitute the given values into the formula:

Moles = 2.4M x 0.25 L
Moles = 0.6 moles

Therefore, 0.6 moles of HNO3 are required to make 250mL of a 2.4M solution.

For the second question, the same formula can be used. To calculate the number of grams of KOH required to make a 0.50M solution in 125mL, you need to determine the number of moles first.

Moles = Concentration (M) x Volume (L)

Convert the volume from milliliters to liters:

125 mL = 125/1000 = 0.125 L

Then, substitute the given values into the formula:

Moles = 0.50M x 0.125 L
Moles = 0.0625 moles

To find the grams of KOH, you need to know its molar mass. The molar mass of KOH is:

K (39.10 g/mol) + O (16.00 g/mol) + H (1.01 g/mol) = 56.11 g/mol

Now, multiply the number of moles by the molar mass of KOH:

Grams = Moles x Molar mass
Grams = 0.0625 moles x 56.11 g/mol
Grams = 3.505 g

Therefore, you require 3.505 grams of KOH to make 125mL of a 0.50M solution.

To calculate the number of moles required to make a certain concentration of a solution, you need to use the formula:

Moles = Concentration (M) * Volume (L)

For the first question, you want to find how many moles of HNO3 are required to make a 2.4M solution in 250mL.

Step 1: Convert the volume to liters:
250 mL = 250/1000 = 0.250 L

Step 2: Use the formula to calculate the moles:
Moles = 2.4M * 0.250 L = 0.6 moles

Therefore, you would need 0.6 moles of HNO3 to make 250mL of a 2.4M solution.

1. moles = M x L.

2. moles = M x L. Then moles = grams/molar mass.