posted by Susan .
A sample of 8 grams of NaOH is dissolved into 599 mL of aqueous 0.250 M NaOH (assume
no volume change). This solution is then
poured into 1.68 gallons of water. (You may
assume that the two volumes can be added.)
What is the concentration of NaOH in the
Answer in units of M
What volume of ethanol must be diluted with
water to prepare 674 mL of 0.854 M solution?
The density of ethanol is given as 0.789 g/mL.
Answer in units of mL
Work with mols.
mols NaOH in 8g = grams/molar mass = ?
mols NaOH in 599 mL of 0.250M = M x L = ?
Total mols NaOH = ?
Now total volume is
599 mL + 1.68 gallons. Convert mL to L and convert 1.68 gallons to L. Add to find total L.
Then (NaOH) in final solution is mols/L