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Chemistry

A Level

Explain why sulfur deviates from the general trend in ionisation energies across period 3.

Sulfur has the electronic structure [Ne]3s2 3p4. This means there are 2 electrons in the same p orbital. These repel each other making it easier to remove the electron causing the ionisation energy to be ...

Answered by Angus M. • Chemistry tutor

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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.

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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

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Explain in terms of bonding and structure the properties of graphite given that it is a good conductor, soft and has a very high melting point

It is a good conductor as there are delocalised electrons. It is soft as the layers are only held together by weak Van der Waals' forces so they can slide over one another. It has a high melting point as ...

Answered by Isabel C. • Chemistry tutor

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State and explain the general trend in first ionisation energy across Period 3

As you go across period 3 there is a general increase in the trend of the first ionisation energy. This is because the atoms have a greater charge on the nucleus (this means they have more protons). Howev...

Answered by Helen B. • Chemistry tutor

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