Posted by Jessica on .
an aqueous solution solution of sodium borate is sometimes used to to fireproof wood.
a. what is the molarity of 2.50 L of solution that contains 1.85 moles of sodium borate?
b. what is the molarity of 45.0 L of solution that contains 6.78 kg of sodium borate?
c. how manny moles of sodium borate are in 600.0 mL of a 1.57 M sodium borate solution?
d. a chemist needs 50.8 g of sodium borste for a reaction. How many mL of 1.87 M solution contain this mass?

chemistry 
DrBob222,
An aqueous solution solution of sodium borate is sometimes used to to fireproof wood.
a. what is the molarity of 2.50 L of solution that contains 1.85 moles of sodium borate?
M = mols/L
b. what is the molarity of 45.0 L of solution that contains 6.78 kg of sodium borate?
Convert kg to grams, then
mols sodium borate = grams/molar mass.
Then M = mols/L
c. how many moles of sodium borate are in 600.0 mL of a 1.57 M sodium borate solution?
mols = M x L
d. a chemist needs 50.8 g of sodium borste for a reaction. How many mL of 1.87 M solution contain this mass?
How many mols do you need? That's mols = grams/molar mass. solve for mols. Then
M = mols/L; rearrange to L = mols/M. You have mol and M, solve for L and convert to mL.