How many grams of sodium chloride are needed to prepare 250 mL of a 2% solution?
find the moles of NAOH =250*0.20/1000
no of moles = 0.05
moles=mass/molar mass
so,
mass=moles*molar mass
molar mass of NAOH is =40
so,mass=0.05*40 =2g
mass of NAOH needed is 2g {answer}
3nx ...
58/2*100 = 2900 grams
To find out how many grams of sodium chloride are needed to prepare a 2% solution, we need to follow a few steps:
Step 1: Determine the desired volume of the solution (in mL). In this case, it is given as 250 mL.
Step 2: Calculate the amount (in grams) of sodium chloride required for a 2% solution.
A 2% solution means that in 100 mL of solution, there are 2 grams of sodium chloride. So, we need to find out how many grams are needed for 250 mL.
First, we find out how many grams are needed for 100 mL:
2 grams/100 mL = 0.02 grams/mL
Then, we can calculate the total amount of sodium chloride needed for 250 mL:
0.02 grams/mL x 250 mL = 5 grams
Therefore, you would need 5 grams of sodium chloride to prepare a 250 mL 2% solution.