Question

How many grams of nickel (II) chloride hexahydrate are required to prepare 250. mL of aqueous solution whose concentration is 0.255 M? The molar mass of nickel (II) chloride hexahydrate is 237.69 g mol−1.

Answer 1

Approximately 15.17 grams of nickel (II) chloride hexahydrate are needed to prepare a 250 mL solution with a concentration of 0.255 M.

Step-by-step explanation:

To calculate the mass of nickel (II) chloride hexahydrate needed to prepare a 0.255 M solution, you need to use the formula:

mass = molarity (M) × volume (L) × molar mass (g/mol)

First, convert the volume from milliliters to liters:

250 mL = 0.250 L

Then, use the given molarity and molar mass:

mass = 0.255 M × 0.250 L × 237.69 g/mol

mass = 15.1693125 grams

Therefore, you would need approximately 15.17 grams of nickel (II) chloride hexahydrate to prepare the solution.

Answer 2

Answer: 15.2 grams

Step-by-step explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

`Molarity=(n* 1000)/(V_s)`

where,

n= moles of solute

`V_s` = volume of solution in ml

moles of solute (nickel (II) chloride hexahydrate ) =
`\farc{\text{given mass}}{\text {Molar mass}}=(xg)/(237.69g/mol)`

Putting the values , we get

`0.255= (x* 1000)/(237.69* 250)`

`x=15.2g`

Thus 15.2 grams of nickel (II) chloride hexahydrate are required to prepare 250. mL of aqueous solution whose concentration is 0.255 M.