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3 years ago

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A piston in a heat engine does 500 joules of work, and 1400 joules of heat are added to the system. Determine the change in inte

rnal energy and explain how this example demonstrates the conservation of energy.

1 answer:

san4es73 [151]3 years ago

8 0

Answer : The change in internal energy is, 900 Joules.

Solution : Given,

Heat given to the system = +1400 J

Work done by the system = -500 J

Change in internal energy is equal to the sum of heat energy and work done.

Formula used :

$\Delta U=q+w$

where,

$\Delta U$ = change in internal energy

q = heat energy

w = work done

As per question, heat is added to the system that means, q is positive and work done by the system that means, w is negative.

Now put all the given values in the above formula, we get

$\Delta U=(+1400J)+(-500J)=900J$

Therefore, the change in internal energy is 900 J.

The change in internal energy depends on the heat energy and work done. As we will change in the heat energy and work done, then changes will occur in the internal energy. Hence, the energy is conserved.

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A sample of a pure compound that weighs 60.3 g contains 20.7 g Sb (antimony) and 39.6 g F (fluorine). What is the percent compos

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Answer:

The percent composition of fluorine is 65.67%

Explanation:

Percent Composition is a measure of the amount of mass an element occupies in a compound. It is measured in percentage of mass.

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The calculation of the percentage composition of an element is made by:

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<u><em>The percent composition of fluorine is 65.67%</em></u>

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<h3>Explanation</h3>

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