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Elanso [62]
2 years ago
12

Please help i need to do good in this class

Chemistry
1 answer:
ioda2 years ago
8 0

Answer:

Explanation:

di) number of protons is 12 for all, number of neutrons is 13 for mg- 25 and 14 for mg-26

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Based on the bond energies for the reaction below, what is the enthalpy of the reaction?HC≡CH (g) + 5/2 O₂ (g) → 2 CO₂ (g) + H₂O
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1219.5 kj/mol

Explanation:

To reach this result, you must use the formula:

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BE C = C: 839 kj / mol

BE C-H: 413 Kj / mol

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BE C = O = 799 Kj / mol

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Now you must replace the values in the above equation, the result of which will be:

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8 0
2 years ago
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D

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topjm [15]

Answer : The number of moles in 369 grams of calcium hydroxide is, 4.98 moles

Explanation : Given,

Mass of calcium hydroxide = 369 g

Molar mass of calcium hydroxide = 74.093 g/mole

Formula used :

\text{Moles of calcium hydroxide}=\frac{\text{Mass of calcium hydroxide}}{\text{Molar mass of calcium hydroxide}}

Now put all the given values in this formula, we get the moles of calcium hydroxide.

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Therefore, the number of moles in 369 grams of calcium hydroxide is, 4.98 moles

7 0
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