what is the total # of grams of NaOH(formula mass=40) needed to make 1.0 liter of a 0.20 M solution

a. 80.g
b. 2.0g
c. 8.0g
d. 20.g

Go back to the molarity definition.

is the answer b

molarity = #mols/L
0.20 M means we want # mols in 1 L to be 0.20 mols. grams = mols x molar mass = 0.2 x 40 = ??

C?

0.20 x 40 = 8.0g

Yes, you are correct. The answer is c. 8.0g.

To determine the total number of grams of NaOH needed to make a 0.20 M solution, you need to use the molarity definition. Molarity is defined as the number of moles of solute per liter of solution.

In this case, we want a 0.20 M solution of NaOH in 1.0 liter. We know that the molar mass of NaOH is 40 g/mol. So, we can use the formula:

grams = moles x molar mass

To find the number of moles, we can rearrange the molarity formula:

moles = molarity x volume (in liters)

Since we want 0.20 moles in 1.0 liter, the number of moles is 0.20 x 1 = 0.20 moles.

Now, we can substitute this value into the grams formula:

grams = 0.20 moles x 40 g/mol = 8.0g

Therefore, the total number of grams of NaOH needed to make a 0.20 M solution is 8.0g.

Yes, the correct answer is c) 8.0g. To calculate the mass of NaOH needed to make a 0.20 M solution, you can use the formula mass = moles x molar mass. In this case, moles is equal to the molarity (0.20 M) multiplied by the volume in liters (1.0 L), which gives 0.20 moles. Then, you can multiply the moles (0.20) by the molar mass of NaOH (40 g/mol) to find the total mass needed, which equals 8.0g.