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Tanzania [10]
3 years ago
9

How did oxygen come up to make 21% of the earth's present atmosphere?

Chemistry
1 answer:
MakcuM [25]3 years ago
4 0
Tiny organisms known as cyanobacteria, or blue-green algae.
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When baking soda and vinegar react, the product includes bubbles. what is most likely occurred
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Explain the three laws of chemical reaction in detain gilling examples​
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Why are alkali metals so reactive?
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8 0
2 years ago
From the lists of available reagents select the one(s) you would use to in a preparation of acetophenone (phenyl methyl ketone)
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Explanation:

The above 3 steps will yield acetophenone from methylbenzoate

3 0
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