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PSYCHO15rus [73]
3 years ago
14

Saltpeter is a compound made of potassium(K), nitrogen(N), and oxygen(O). Every 100.0g of saltpeter contains 38.67g potassium an

d 13.86g nitrogen. What is the mass of oxygen contained in 285.0mg of saltpeter? Answer needs to be in grams
Chemistry
1 answer:
Oksanka [162]3 years ago
7 0
Use a proportion ... 
<span>100.0g - 38.67g - 13.86g = 47.47g Oxygen </span>
<span>285.0 mg = 0.285g </span>
<span>47.47/100 = x/0.285g </span>
<span>x = ( 47.47/100) X 0.285g </span>
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Hello there!  

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