How many grams of K2Cr2O7 are required to prepare 500 ml of a 0.13 N solution?

0.13N= # of equivalents/500 x10^-3 L, solving for # of equivalents

# of equivalents in 0.13N=(0.13N)(500 x 10^-3L)

# of equivalents in 0.13N= g of solute/49.03g, solve for grams of solute,

(49.03g, solve )*(# of equivalents in 0.13N)= g of solute

To calculate the number of grams of K2Cr2O7 required to prepare 500 ml of a 0.13 N solution, you'll need to follow these steps:

1. Identify the equation to calculate the number of grams.
2. Determine the molar mass of K2Cr2O7.
3. Convert the given volume from milliliters to liters.
4. Calculate the number of moles required for the desired concentration of the solution.
5. Use the molar mass and the number of moles to determine the grams of K2Cr2O7 needed.

Let's go through each step in detail:

1. The equation you can use is: Concentration (N) = Number of moles / Volume (in liters).

2. The molar mass of K2Cr2O7 can be calculated by adding up the atomic masses of its elements:
Molar mass(K2Cr2O7) = (2 * atomic mass of K) + (2 * atomic mass of Cr) + (7 * atomic mass of O)

By looking up the atomic masses of the elements, the molar mass of K2Cr2O7 is:
Molar mass(K2Cr2O7) = (2 * 39.10 g/mol) + (2 * 52.00 g/mol) + (7 * 16.00 g/mol)

3. The given volume is 500 ml. To convert it to liters, divide it by 1000:
Volume (in liters) = 500 ml / 1000 = 0.5 liters

4. To find the moles of K2Cr2O7 required, rearrange the equation for concentration:
Number of moles = Concentration (N) * Volume (in liters)

Substituting the values, we get:
Number of moles = 0.13 N * 0.5 liters

5. Calculate the actual number of grams of K2Cr2O7 required using the molar mass and the number of moles:
Grams of K2Cr2O7 = Number of moles * Molar mass(K2Cr2O7)

Substituting the values, we get:
Grams of K2Cr2O7 = (0.13 N * 0.5 liters) * Molar mass(K2Cr2O7)

Calculate the result, and you will have the quantity of K2Cr2O7 required in grams to prepare a 500 ml solution with a concentration of 0.13 N.