So i been trying to solve this question like for ever! so i hope you guys can help me , here is the question :

the volume of a seawater on earth is about 330,000,000 mi3. if seawater is 3.5% sodium chloride by mass and has a density of 1.03g/mL, what is the approximate mass of sodium chloride, in tons, dissolved in the seawater on earth. (1 ton = 2000lb)

1 answer

Convert 330,000 cubic miles to cc. You can do it the hard way
5,280 ft/mile --this term is cubed.
12 inches/foot --this term is cubed.
2.54 cm/inch--this term is cubed.
OR you can go to www.google.com and type into the search box the following without the quotation marks.
"330,000 cubic miles to cc" and hit enter.
I think the answer is 1.375 x 10^21 cc.
mass = volume x density. You know volume in cc and you know density in g/cc, calculate mass. Multiply by 0.035 to convert to grams NaCl in the seawater. Now convert grams to pounds (again go to google to convert) and divide by 2000 to convert to tons. Or easier still is to use google to convert from grams to tons. You may need to specify US tons since a metric tons is not the same.