Answer:
Q = -33.6kcal .
Explanation:
Hello there!
In this case, according to the equation for the calculation of the total heat of reaction when a fixed mass of a fuel like ethane is burnt, we can write:

Whereas n stands for the moles and the other term for the enthalpy of combustion. Thus, for the required total heat of reaction, we first compute the moles of ethane in 3 g as shown below:

Next, we understand that -337.0kcal is the heat released by the combustion of 1 mole of ethane, therefore, to compute Q, we proceed as follows:

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Answer:

Explanation:
Hello!
In this case, since the percent water is computed by dividing the amount of water by the total mass of the hydrate; we infer we first need the molar mass of water and that of the hydrate as shown below:

Thus, the percent water is:

So we plug in to obtain:

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Answer:
false
in chemical reaction element doesnot change into another
Explanation:
The answer is: "10" .
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" A centimeter and millimeter differ from each other by a factor of "10" .
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Note:
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100 cm = 1 m
1000 mm = 1m
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100 * (10) = 1000 .
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The answer is: "10".
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" A centimeter and millimeter differ from each other by a factor of "10".
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