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Chemistry
A Level

Why is phenol more reactive than benzene?

Phenol (which is a benzene ring with one substituted carbon with a hydroxyl or alcohol group) does not require a halogen carrier to be halogenated whereas benzene itself cannot react with a halogen alo...

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Answered by Thomas N. Chemistry tutor
40190 Views

What is the difference between a nucleophile and an electrophile?

A nucleophile is a molecule or ion that donates a pair of electrons to form a new covalent bond. It is strongly attracted to a region of positive charge. Common nucleophiles include hydroxide ions; due...

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Answered by Liam M. Chemistry tutor
22478 Views

What is a mole?

A mole is a unit of measurement for the amount of a substance. One mole is 6.02 x 10^23 particles in a substance, known as Avogadro's constant. This is because this is the number of atoms in  <...

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Answered by Liam M. Chemistry tutor
3765 Views

Proteins are an important part of a healthy diet because they provide essential amino acids. (a) State what is meant by an essential amino acid.

 There are 20 amino acids, and they can be classified as essential or non-essential – if they are non-essential they can be synthesised by the human body...

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Answered by Darragh C. Chemistry tutor
3638 Views

The recommended daily allowance of methionine for an adult is 15 mg per kg of body mass. Tuna contains 755 mg of methionine per 100 g portion. Calculate the mass, in grams, of tuna that would provide the RDA of methionine for a 60 kg adult.

15mg per kilo recommended dose 15x60 = 900mg recommended dose for a 60kg adult There is 755mg per 100g portion of tuna So 900/755 = 1.19 times the amount in 100g of tuna is the recommended dose 1.19 x 100...

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Answered by Darragh C. Chemistry tutor
5617 Views

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