chemistry help :)

Question

If you want to make a 0.197 M solution using 4.40 grams of sodium hydroxide, how many milliliters does the solution need to occupy?

Answer 1

Hi Molly!

For this question, our first step is figure out how many moles of sodium hydroxide (NaOH) we have. To do this, we need to divide the number of grams we are given (4.4g) by the molar mass of NaOH that we can use the periodic table to find (40g/mol), which gives us 0.11 moles of NaOH. Our concentration in molarity can be broken down to mol/L, so now we're just doing some basic algebra to solve for volume, since we know what concentration we want, and we know how many moles we have:

0.197M = 0.11mol NaOH/ xL ----> xL = 0.11mol NaOH/0.197M --> x = 0.56L.

The question asked for milliliters, so we multiply by 1000 to get L to mL:

0.56L x 1000 = 560mL

Hope this helps!