What are the empirical formulas of substances with the following ...

Question

What are the empirical formulas of substances with the following mass percent compositions? 
(c) Sodium thiosulfate (photographic “fixer”): 30.36% O, 29.08% Na, 40.56% S

Accepted Answer

Hello. Everyone in this question were given the following percentages and were asked the empirical formula, There's gonna be a total of 100%. So we're gonna assume that we have 100 g of the compound. So the first thing we need to do is convert the percentages into grams, 26.41 g of sodium. And now we need to convert the grams into moles only one mole Of sodium, the molar mass which is 22.99 g. And this will give us 1.15 moles of sodium. Then we have 36.84 g a sulfur. And in one mole Of sulfur we have 32.07 g of sulfur. And this will give us 1.15 moles of sulfur. And then we have 36.76 g of oxygen. And in one mole of oxygen F 16 g. And this will give us 2.3 moles of oxygen. And now we need to find the smallest ratio by dividing by the smallest number of moles. So for sodium With 1.15 By about 1.15. Let's give us one. So for 1.155 x 1.15. Let's give us one for oxygen. Have 2.35 by 1.15. And this will give us two. We're gonna have a. S. 02. It's gonna be D. Thanks for watching my video and I hope it was helpful

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