Question

Calculate the mass of naoh needed to prepare 100. ml of 0.15m solution.

Answer 1

To prepare 100 mL of a 0.15 M NaOH solution, you will need approximately 0.60 g of NaOH.

Step-by-step explanation:

To calculate the mass of NaOH needed to prepare a 0.15 M solution, we need to use the formula:

Mass (g) = Molarity (M) x Volume (L) x Molar Mass (g/mol)

In this case, the molarity is 0.15 M and the volume is 100 mL (or 0.1 L). The molar mass of NaOH is 22.990 + 15.999 + 1.008 = 39.997 g/mol.

Mass (g) = 0.15 M x 0.1 L x 39.997 g/mol = 0.5999 g, which can be rounded to 0.60 g.

Answer 2

as, molarity = number of moles of solute / volume of solution(in liter)
here, volume is 500ml or 0.5 l
molarity is 0.04M
no. of moles of solute = mass of NaOH required (x) / gram atomic mass of NaOH(=40)

therefore, 0.04 = x / (40 x 0.5)
x = 0.8gram