How many grams of potassium dichromate are required to prepare a 250ml solution of whose concentration is 2.16m.?
Did you know that m stands for Molality and M stands for Molarity? From the wording I assume you mean M but moles is calculated the same.
You want how many moles? That's M x L = 2.16 x 0.250 = ? Then
grams = moles K2Cr2O7 x molar mass K2Cr2O7.
Well, if you're feeling a little thirsty, I can definitely help you with your chemistry question! So, let's calculate the grams of potassium dichromate needed to prepare this solution.
To find the answer, we need to use the equation:
Molarity (M) = moles of solute / volume of solution (L)
First, we need to convert the given volume from milliliters to liters:
250 ml = 0.250 L
Now, let's rearrange the equation to solve for moles of solute:
moles of solute = Molarity (M) × volume of solution (L)
So, with the given molarity of 2.16 M and volume of 0.250 L, we can calculate the moles of solute like this:
moles of solute = 2.16 M × 0.250 L = 0.54 mol
Now it's time to find the molar mass of potassium dichromate. Potassium has a molar mass of approximately 39.1 g/mol, and dichromate has a molar mass of 52 g/mol. Since there are two potassium ions in potassium dichromate, we need to multiply the molar mass of potassium by 2:
Molar mass of potassium dichromate = (2 × 39.1 g/mol) + 52 g/mol = 130.2 g/mol
Finally, let's calculate the grams of potassium dichromate needed:
grams of potassium dichromate = moles of solute × molar mass of potassium dichromate
grams of potassium dichromate = 0.54 mol × 130.2 g/mol = 70.308 g
Therefore, approximately 70.308 grams of potassium dichromate are required to prepare a 250 ml solution with a concentration of 2.16 M. And remember, if chemistry ever feels confusing, just think of it as a way to make sure we don't blow things up!
To calculate the number of grams of potassium dichromate required to prepare a 250 mL solution with a concentration of 2.16 M, you need to use the formula:
Molarity (M) = moles of solute / liters of solution
First, let's rearrange the formula to solve for moles of solute:
moles of solute = Molarity (M) × liters of solution
Given:
Molarity (M) = 2.16 M
Liters of solution = 250 mL
To convert 250 mL to liters, divide it by 1000:
Liters of solution = 250 mL / 1000 mL/L = 0.25 L
Now, substitute the given values into the formula:
moles of solute = 2.16 M × 0.25 L
moles of solute = 0.54 moles
To convert moles to grams, you need to know the molar mass of potassium dichromate. The molar mass of potassium dichromate (K2Cr2O7) is approximately 294.18 g/mol.
Now, calculate the grams of potassium dichromate required:
grams of potassium dichromate = 0.54 moles × 294.18 g/mol
grams of potassium dichromate ≈ 158.80 grams
Therefore, approximately 158.80 grams of potassium dichromate are required to prepare a 250 mL solution with a concentration of 2.16 M.
To calculate the number of grams of potassium dichromate required to prepare a 250mL solution with a concentration of 2.16M, we need to use the formula:
moles = concentration × volume
First, let's convert the volume to liters:
250 mL = 250/1000 = 0.25 L
Now, we can rearrange the formula to solve for moles:
moles = concentration × volume
moles = 2.16 M × 0.25 L
Calculating the moles:
moles = 0.54 mol
Next, we need to determine the molar mass of potassium dichromate (K2Cr2O7). Adding up the atomic masses:
K: 39.10 g/mol × 2 = 78.20 g/mol
Cr: 52.00 g/mol × 2 = 104.00 g/mol
O: 16.00 g/mol × 7 = 112.00 g/mol
Total molar mass: 78.20 g/mol + 104.00 g/mol + 112.00 g/mol = 294.20 g/mol
Finally, we can calculate the grams of potassium dichromate required:
grams = moles × molar mass
grams = 0.54 mol × 294.20 g/mol
grams ≈ 158.93 g
Therefore, approximately 158.93 grams of potassium dichromate are required to prepare a 250 mL solution with a concentration of 2.16M.