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Lelechka [254]
3 years ago
6

Determine the number of atoms present in 4.5 mols of Calcium

Chemistry
1 answer:
Nuetrik [128]3 years ago
8 0

Answer:

1 mole : 6,022 * 10^23  = 4.5 moles : X

X = (6.022 * 10^23 * 4.5)/1 = 2.7099 * 10^24 atoms

Explanation:

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How many kj of heat are needed to completely melt 32.3 g of h2o, given that the water is at its melting point? the heat of fusio
timurjin [86]

Answer: fourth option, 10.8 kJ


Explanation:


The <em>heat of fusion</em>, also named latent heat of fusion, is the amount of heat energy required to change the state of a substance from solid to liquid (at constant pressure).


The data of the <em>heat of fusions</em> of the substances are reported in tables and they can be shown either per mole or per gram of substance.


In this case we have that the<em> heat of fusion for water </em>is reported per mole: <em>6.02 kJ/mole</em>.


The formula to calculate <em>how many kJ of heat (total heat) are needed to completely melt 32.3 g of water, given that the water is at its melting point</em> is:

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The calculations are:

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5 0
3 years ago
Read 2 more answers
How to solve 2 and 3
GarryVolchara [31]
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Which of the following is an example of an action done to maintain homeostasis?
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pochemuha
C.) iron oxide <span>is responsible for the red color of Mars.

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The half life of Radon-222 is 3.8 days. If you have a 90.0g sample of Radon-222 in the lab, how much will be left after 19 days?
statuscvo [17]

Answer:

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Explanation:

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5 0
3 years ago
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