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Chemistry

A Level

What is the definition of a H-Bond?

A H-bond is an attraction between molecules. It is therefore an intermolecular force, and in fact one of the strongest. Molecules which exhibit H-bonding must contain a hydrogen that is directly bo...

Answered by Oliver M. • Chemistry tutor

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Why does Phosphorus have a higher melting point than Chlorine?

Phosphorus exists as P₄and chlorine as Cl₂so elemental phosphorus is a bigger molecule than chlorine. Neither of these molecules has a dipole so both have only induced dipole-dipol...

Answered by Rory S. • Chemistry tutor

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Describe how you could form ethyl ethanoate using only ethanol as the starting material. Include all relevant reagents and conditions.

To perform the esterification, we are going to need to react a carboxylic acid with an alcohol (in this case). We already have the correct alcohol: ethanol. Therefore to get ethanoic acid we must oxidise ...

Answered by Callum M. • Chemistry tutor

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Explain the difference in reactivity between benzene and phenol with bromine?

Phenol reacts with bromine at room temperature with no catalyst as the hydroxyl group activates the ring by donating a pi electron. This donated electron increases the electron density of the ring hence a...

Answered by Reece L. • Chemistry tutor

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A buffer solution was formed by mixing 20.0 cm^3 of sodium hydroxide solution of concentration 0.100 mol dm^–3 with 25.0 cm^3 of ethanoic acid of concentration 0.150 mol dm^–3. CH3COOH + NaOH---CH3COONa + H2O Calculate the pH of this buffer solution.

Ka for ethanoic acid = 1.74 × 10–5 mol dm^–3 also given in question. moles = concentration x volume / 1000Ka = [H+] [A-]/[HA]pH = -log [H+]
initial moles:NaOH: 20x0.1/1000 = 0.002molCH_...

Answered by • Chemistry tutor

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