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Chemistry

A Level

Explain what is meant by the term "rate of reaction".

A change in the concentration of reactants or products per unit time

Answered by Filip H. • Chemistry tutor

1816 Views

Describe the arrangement of protons, neutrons and electrons in an atom of Neon (Atomic No. 10, Atomic Weight 20.18). You may use diagrams to aid you.

A fully-marked answer would contain each of these points, or clear diagram equivalent
10 protons10 neutrons10 electrons, arranged with 2 in the inner 's' shell and 8 in the 'p' shell

Answered by Zach L. • Chemistry tutor

2269 Views

Name the three steps in free radical substitution and give an example equation for each

Initiation: Cl2 (+UV) -> Cl + Cl Propagation: Cl + CH4 -> HCl + CH3 Termination: CH3 + Cl -> CH3Cl

Answered by Arwen G. • Chemistry tutor

1551 Views

A reaction, A + B -> C, is considered second order with respect to A and first order with respect to B. What is the effect of simultaneously doubling the concentration of A and B on the rate of reaction?

"second order with respect to A" tells us that doubling the concentration of A will cause the reaction rate to increase by a factor of 4."first order with respect to B" then tells us t...

Answered by HENRY J. • Chemistry tutor

1709 Views

Discuss the 2 most-commonly encountered representations of benzene, providing an advantage and disadvantage for each

Kekule structure advantages: Useful for mechanistic understanding, can push arrows to advise likely regiochemistry. Disadvantages: ignores aromatic stablisation, drawn structure much higher energy than ac...

Answered by William H. • Chemistry tutor

3224 Views