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Leokris [45]
3 years ago
12

WORTH 20 POINTS HELP PLEASE

Chemistry
1 answer:
Damm [24]3 years ago
5 0

Answer:

The answers to your questions are below

Explanation:

Physical change is when matter changes its form but is still the same substance.

Chemical change is when matter changes its composition.

iron and oxygen from rust  It's a chemical change because iron and oxygen form a new compound different from the reactants.

iron is denser brightly when ignited . This is a chemical property because iron reacts with oxygen.

oil and water do not mix it's a physical change, oil and water are in touch but they do not react.

mercury melts at -39°C it's a physical property because mercury changes from solid to liquid but it still is mercury.

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An object is dropped from a height of 150m. What's the object's terminal velocity (the velocity with which the object hits the g
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A reaction produces 10.5 L if oxygen, but was supposed to produce 1 mol of oxygen. What is the percent yield ? (One mole of any
Rzqust [24]
To answer this item, we assume that oxygen behaves ideally such that it is able to fulfill the following equation,

 PV = nRT

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7 0
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Explanation:

32

2H

2

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From the balanced chemical equation,

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