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Describe how and explain why vegetable oils are hardened for use in foods. [5 marks]

Hydrogenation is used to add hydrogens to the vegetable oil molecules. This process gets rid of the double bonds in the molecular structure, making the molecules saturated, which lowers the melting point ...

Answered by Nadia M. • Chemistry tutor

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I don't understand why carbon forms 4 bonds but nitrogen doesn't form 5.

Carbon has 4 electrons in its outer shell, a pair in the 2s and two unpaired electrons in the 2p. For covalent bonds to form, each atom must donate one unpaired electron. Carbon makes four bonds because i...

Answered by Ryan H. • Chemistry tutor

9119 Views

Elements in the periodic table show a trend in atomic radius. State and explain the trend in atomic radius from Li to F.

The atomic radii of an atom is essentially the distance from the centre of the nucleus to the outer shell of electrons- so atoms that are very small and have a small distance from the nucleus to the outer...

Answered by Demi S. • Chemistry tutor

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Molecules of hydrogen chloride, HCl, and molecules of fluorine, F2, contain the same number of electrons. Hydrogen chloride boils at –85 °C and fluorine boils at –188 °C. Explain why there is a difference in the boiling points of HCl and F2.

F2 has temporary dipole-dipole interactions known as van der Waals’ forces. Whilst HCl has permanent dipole-dipole interactions. The intermolecular forces in HCl are stronger than that in F2 (permanent di...

Answered by Freddie G. • Chemistry tutor

6917 Views

What is the equilibrium constant?

Imagine a bathtub that someone forgot to plug, but they left the tap open. If the water from the tap is running fast enough, after some time the speed at which water drains and the speed at which water fi...

Answered by Wojciech L. • Chemistry tutor

2103 Views