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Chemistry

A Level

Explain the resistance to bromination of benzene in comparison to phenol.

In phenol, one of the lone pairs of electrons in a p-orbital of the oxygen atom in the -OH group overlaps with the delocalised ring of electrons in the ring. This lone pair is partially d...

Answered by Cerys H. • Chemistry tutor

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Explain why benzene requires use of a halogen carrier catalyst to react with bromine while phenol does not.

The oxygen atom in the phenol molecule has a lone pair of electrons. These electrons become delocalised into the aromatic ring, increasing its electron density. This activates the ring. This causes Br

Answered by Aidan M. • Chemistry tutor

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Given the following equilibrium: H2O + H2O <-> H3O+ + OH- and the Kw = 10^-14, determine the concentration of OH- species after the addition of 1 mmol of HCl to 1 L of neutral water.

As HCl is a strong acid, it will fully dissociate in water, releasing 1 mmol of H⁺, which will be the final concentration of protons in solution. The autoprotolysis equilibrium of water (or K

Answered by Samuel N. • Chemistry tutor

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The reversible reaction of sulfur dioxide and oxygen to form sulfur trioxide is shown below. 2SO2(g) + O2(g) 2SO3(g) An equilibrium mixture contains 2.4mol SO2, 1.2mol O2 and 0.4mol SO3. The total pressure is 250atm. What is the p(SO3)?

First step is to calculate the mole fraction of the SO3. This can be done by dividing the moles of SO3 by the total moles at equilibrium to give 0.4/4. This is then multiplied by the total pressure at equ...

Answered by Saji M. • Chemistry tutor

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What are moles and how do you calculate them?

Well this depends whether you require the moles of gas, solid or solution as to which equation you use, moles relate the mass of the atom of interest to that of the number of atoms in 12 grams of carbon-1...

Answered by Benjamin T. • Chemistry tutor

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