Question

How many moles and grams of nacl are there in 250 cc of a 0.5 m nacl solution?

Answer 1

Answer:

Given, volume of solution is 250ml or 0.25 liter.

Molarity of NaCl = 0.50M

Now, according to molarity formula

M = n/V(in L)

where , n = no. of mole of solute(NaCl)

put the value

0.5 = n/0.25

=> n = 0.5×0.25

=> n = 0.125mole

So, number of mole of solute (NaCl) is 0.125mole present in solution .

Now , molecular mass of NaCl is

NaCl = 23+ 35.5 = 58.5

Now, according to formula

number if mole = mass of NaCl/molecular mass

=> 0.125 = mass of NaCl/58.5

=> mass of NaCl = 0.125×58.5 = 7.3125g

Hence, 7.3125 grams of sodium chloride is present in 250mL.

Answer 2

Answer:

Given, volume of solution is 250ml or 0.25 liter.

Molarity of NaCl = 0.50M

Now, according to molarity formula

M = n/V(in L)

where , n = no. of mole of solute(NaCl)

put the value

0.5 = n/0.25

=> n = 0.5×0.25

=> n = 0.125mole

So, number of mole of solute (NaCl) is 0.125mole present in solution .

Now , molecular mass of NaCl is

NaCl = 23+ 35.5 = 58.5

Now, according to formula

number if mole = mass of NaCl/molecular mass

=> 0.125 = mass of NaCl/58.5

=> mass of NaCl = 0.125×58.5 = 7.3125g

Hence, 7.3125 grams of sodium chloride is present in 250mL.

Explanation: