How many grams of NaOH would you dissolve in pure water to make 400 mL of a 2.5% NaOH solution ? MW of NaOH = 40 g/mol
Please help, im currently stuck
If milk has a density of 1.03 g/mL, what is the mass of 9.00 qt, reported in kilograms?
Is that % w/v or w/w. I will assume w/v.
2.5% w/v means 2.5 g/100 mL.
You want 400 mL so
2.5 x (400/100) = ?
If you want an answer it is better to post a new question and not piggy back on another student's question.
1. Convert 9.00 qt to mL. 1 qt = 946 mL.
2. Then mass = volume x density
Substitute and solve for mass (n grams).
3. Convert grams to kg.
To calculate the amount of NaOH needed to make a 2.5% solution, we can follow these steps:
Step 1: Determine the mass/volume relationship:
2.5% NaOH solution means 2.5 grams of NaOH per 100 mL of solution. We need to find the amount of NaOH needed for 400 mL of solution.
Step 2: Use the given molecular weight (MW) to calculate the grams of NaOH in 100 mL:
MW of NaOH = 40 g/mol
2.5 grams NaOH / 100 mL = x grams NaOH / 400 mL
Step 3: Solve for x (grams of NaOH in 400 mL of solution):
Cross multiply and solve for x:
2.5 grams NaOH * 400 mL = x grams NaOH * 100 mL
x = (2.5 grams NaOH * 400 mL) / 100 mL
Step 4: Calculate the final result:
x = 10 grams
Therefore, you would need to dissolve 10 grams of NaOH in pure water to make a 400 mL of a 2.5% NaOH solution.