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Mamont248 [21]
3 years ago
6

If a substance has a half life of 45 days, how much of the original substance would be left after 90 days?

Chemistry
1 answer:
Fofino [41]3 years ago
8 0
U would subtract 90 minus 45 which equals 45
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when 48 .0g of carbon reacts with oxygen gas to form carbon dioxide, no carbon or oxygen is left over. How much oxygen is reacte
Arte-miy333 [17]

Answer:

128g

Explanation:

Given parameters:

Mass of carbon  = 48g

Mass of carbon dioxide  = 176g

Unknown:

Mass of oxygen that reacted  = ?

Solution:

Every chemical reaction must obey the law of conservation of mass. It states that "in a chemical reaction, matter is neither created nor destroyed" .

So;

     Mass of carbon + Mass of oxygen  = Mass of carbon dioxide

Mass of oxygen  = Mass of carbon dioxide  - Mass of carbon

Mass of oxygen  = 176  - 48  = 128g

3 0
3 years ago
A quantity of 1.922 g of methanol (CH3OH) was burned in a constant-volume bomb calorimeter. Consequently, the temperature rose b
dezoksy [38]

Answer:

872.28 kJ/mol

Explanation:

The heat released is:

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moles = 1.992/32.04 = 0.0621 mol

Then the molar heat of combustion of methanol is:

ΔH/moles = 54.1684/0.0621 = 872.28 kJ/mol

5 0
3 years ago
Separate the reaction Cl2 + 2Cs = 2CsCl into its component half reactions.
AveGali [126]
So the question ask to separate the reaction of the element if your problem into its component half reaction and the best answer or the elements are the following: (Cs-> Cs+ + 1e-) x2 and  <span>2e-+Cl2->2Cl-. I hope you are satisfied with my answer and feel free to ask for more </span>
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Answer:

C. Glaciers

Explanation:

Over 68 percent of the fresh water on Earth is found in icecaps and glaciers, and just over 30 percent is found in ground water. Only about 0.3 percent of our fresh water is found in the surface water of lakes, rivers, and swamps.

Hope this helps!

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7 0
2 years ago
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The answer is because they are magnetic B.
5 0
3 years ago
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