To prepare 100g of 19.7% by weight solution of NaOH.how many grams each of NaOH and H2O are needed?
To calculate the amount of NaOH and H2O needed to prepare a 100g solution of 19.7% NaOH, we need to determine the weight of NaOH and H2O in the solution.
Step 1: Calculate the weight of NaOH in the solution
19.7% of 100g is calculated as (19.7/100) * 100g = 19.7g
Step 2: Calculate the weight of H2O in the solution
Since the total weight of the solution is 100g and we have already determined the weight of NaOH to be 19.7g, we can calculate the weight of H2O by subtracting the weight of NaOH from the total weight:
100g - 19.7g = 80.3g
Therefore, to prepare 100g of a 19.7% NaOH solution, you will need approximately 19.7 grams of NaOH and 80.3 grams of H2O.
To prepare a 100g solution of NaOH with a concentration of 19.7% by weight, you will need to calculate the amount of NaOH and water required.
Step 1: Determine the total mass of the solution.
Since the desired solution has a mass of 100g, we can assume that the sum of the masses of NaOH and water will be equal to 100g.
Step 2: Calculate the mass of NaOH required.
To determine the weight of NaOH needed, multiply the total mass of the solution (100g) by the desired concentration of NaOH (19.7%).
(100g) * (19.7/100) = 19.7g
Step 3: Calculate the mass of water required.
To calculate the weight of water needed, subtract the mass of NaOH (found in step 2) from the total mass of the solution.
100g - 19.7g = 80.3g
Therefore, you will need 19.7 grams of NaOH and 80.3 grams of water to prepare a 100g solution of NaOH with a concentration of 19.7% by weight.
%by mass = (mass solute)/(mass solution)
% w/w = 19.7g NaOH in 100 g solution.
% w/w = 19.7 g NaOH in [19.7g NaOH + (100-19.7)g H2O].