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lina2011 [118]
3 years ago
9

HELP PLEASE HELP ME ONLY 2 QUESTIONS

Chemistry
1 answer:
lara [203]3 years ago
4 0

311 are A 326 are O =  637

740 total

637/740 = 0.8608 = 0.861


1 person got an A and didn't study out of 7 total

 so 1/7 and it is dependent





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A 2.026g sample of a hydrate of sodium carbonate (Na2CO3) is heated to remove water. After heating, the mass of the sample is 0.
OLEGan [10]

Answer:

62.98 % of the sample of hydrate is water

Explanation:

Step 1: Data given

Mass of the sample of a hydrate of sodium carbonate (Na2CO3) = 2.026 grams

After heating, the mass of the sample is 0.750 g

Molar mass H2O = 18.02 g/mol

Step 2: Calculate mass of water

Mass water = mass of hydrate - mass of sample after heating

Mass water = 2.026 grams - 0.750 grams

Mass water = 1.276 grams

Step 3: Calculate mass % percent of water

Mass % of water = (mass of water / total mass hydrate) * 100 %

Mass % of water = (1.276 grams / 2.026 grams) *100 %

Mass % of water = 62.98 %

62.98 % of the sample of hydrate is water

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In 1990, the northern spotted owl was listed as endangered. Because of this, millions of acres of forests in the Pacific
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the endangered spices act

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