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Why does a catalyst speed up a chemical reaction?

A catalyst lowers the activation energy of a reaction. It does this by providing an alternative, lower energy pathway for the reaction. An example of this - a catalyst may form a complex with the reactants w...
JL
Answered by Jack L. • Chemistry tutor
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Was anti-Semitism the main reason for Hitler's popularity in the 1930s? - 20marks

First evaluate the spelling, grammar and form of the answer. Ensure that the pupil has a good understanding of how sentences should flow and connect, as well as how to organise their argument. On the one han...
IB
Answered by India B. • History tutor
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In the Haber process, the best yield of ammonia is produced at a low temperature. Explain why

The forward reaction, N 2 (g) + 3H 2 (g) ---> 2NH3(g) is an exothermic reaction. This means that energy is released to the surroundings during the reaction and the reaction has a negative enthalpy change....
MP
Answered by Monique P. • Chemistry tutor
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Expand and simplify 2y+3y(5y+3)

Following the laws of BIDMAS, the bracket needs to be multiplied first (instead of adding 2y and 3y first): 2y + 15y 2 + 9y Simplify by addition of the y's: 15y 2 + 11y Optional: simplify further by grouping...
LJ
Answered by Lucy J. • Maths tutor
5163 Views

A train accelerates from 10 m/s to 50 m/s in 20 seconds. Calculate the Acceleration

The acceleration, in ms - 2 , is defined as the rate of change of velocity, per unit of time. To calculate the trains acceleration, we use the equation Acceleration= Change in velocity/ Time Taken. For this ...
MP
Answered by Monique P. • Physics tutor
14882 Views