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Describe the enthalpy change of formation of butane.

The enthalpy change of formation of butane is the enthalpy produced when one mole of butane is formed from its elements, all under standard conditions and in their standard states.

4C_(s)

Answered by Edward L. • Chemistry tutor

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Explain the melting points of period 3 elements.

Going from Na to Si, the melting point increases. This is because from Na-Al, the charge of the metal ion and the number of delocalised electrons increases so the strength of the metallic bonding increase...

Answered by Amanpreet K. • Chemistry tutor

6069 Views

How do I form a 'si' clause in French?

In English, a sentence like 'If I were rich, I would buy a house.' is an example of an 'if' clause. It is used to describe a hypothetical situation; something that would happen if a certain condition is f...

Answered by Molly L. • French tutor

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Factorize the following expression and solve for x: X^2 +7X +10=0

Answer: (X+5)(X+2)=0 X=-5 or -2 We first look for to numbers that multiply together to make 10 (1 and 10, 2 and 5 are the only pairs) We choose the pair which also adds together to the 2nd term, 7. We...

Answered by James H. • Maths tutor

3887 Views

Why does the breathing rate increase during exercise?

The breathing rate increases at the start of exercise then reaches a peak and plateaus during exercise. After exercise the breathing rate will gradually fall, but this may take several minutes.

Dur...

Answered by Ayushi M. • Biology tutor

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