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Chemistry

A Level

Explain, in terms of atomic energy levels, how an atomic emission spectrum is formed

Absorbed energy results in electron excitation. De-excitation then occurs, whereby electrons fall back down to the ground state. Energy levels are quantised, therefore each line represents a specific freq...

Answered by George C. • Chemistry tutor

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3-Methylpent-2-ene (CH3CH=C(CH3)CH2CH3) reacts with Hydrogen Chloride(HCl) forming a major and minor product. Please name the reaction, draw the mechanism for the formation of the major product and briefly explain why there is a major and a minor product.

This is an example of electrophilic addition.(It's easier to explain with the mechanism drawn) The mechanism proceeds by electrophilic attack of the Hydrogen in HCl originating from the double bond in 3-m...

Answered by Edward H. • Chemistry tutor

11043 Views

Consider the transition metal complex [CoCl3(CO)3]. What is a) The oxidation state of the metal centre. b) The dn configuration of the metal centre. c) The co-ordination number of the metal centre.

a) +3. Cl ligands carry a negative charge while CO ligands are neutral so the all together the ligands have a charge of -3. Since the complex is neutral overall, the metal must cancel out the charge of t...

Answered by Robert S. • Chemistry tutor

7763 Views

Given the reaction: H2SO4 + NaOH --> ? + H2O. (a). Work out the salt produced (?) and (b). calculate the pH of the remaining solution when 1.2 g of NaOH and 4.41 g of H2SO4 were added in a 500 ml solution. Of the unreacted H2SO4 95% dissociated.

(a). Firstly, to work out the product, take 2Na⁺ + SO₂^- --> 2Na₂SO_4...

Answered by Dan W. • Chemistry tutor

5825 Views

Ethanol can be made from the reaction between ethene and water. The reaction is exothermic and occurs at a high temperature. Describe and explain the effect of raising the temperature on the rate of achievement of equilibrium and the equilibrium yield.

The rate of achievement of equilibrium increases. This can be explained by collision theory. Because the temperature is increases the reactants have more energy and therefor the collisions between them be...

Answered by Alex N. • Chemistry tutor

6230 Views