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Describe how and explain why vegetable oils are hardened for use in foods

Vegetable oils are unsaturated because they contain lots of carbon-carbon double bonds. If we react them with hydrogen at 60oC in the presence of nickel catalyst they will become saturated, also called ha...

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.

4C_(s)

Answered by Edward L. • Chemistry tutor

13951 Views

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

5357 Views

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

8096 Views

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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