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3 years ago

PLS HELP: CHEMISTRY

Chemistry

1 answer:

user100 [1]3 years ago

7 0

Answer:

3.59x10^21 molecules

Explanation:

1mole of a substance contains 6.02x10^23 molecules.

Therefore, 1mole of C8H18 will also contain 6.02x10^23 molecules

1mole of C8H18 = (12x8) +(18x1) = 96 + 18 = 114g.

1mole (i.e 114g) oh C8H18 contains 6.02x10^23 molecules.

Therefore, 0.68g of C8H18 will contain = (0.68 x 6.02x10^23)/114 = 3.59x10^21 molecules

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Explanation:

Internal energy change (ΔU) for the reaction of combustion in the bomb calorimeter is:

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Where:

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