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Explain how we can increase the rate of a chemical reaction.(6 marks)

-Increase the concentration (pressure in gases). (1) This increases the likelihood and frequency of collision because the particles of reactant will be closer together (1)-Increase the temperature(1). Thi...

Answered by Ayoyinka O. • Chemistry tutor

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What is periodicity?

Periodicity is the trend in chemical and physical properties of the elements across each period of the periodic table.All elements in a period have the same number of shells, all elements in a group have ...

Answered by Jonathan A. • Chemistry tutor

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The equation for the reaction between ammonia and oxygen is shown. 4NH3(g) + 5O2(g) ⇌ 4NO(g) + 6H2O(g) . Calculate the entropy change of the reaction, using data from the table below.

GAS So / J K^-1 mol^-1 NH3(g) 193 O2(g) 205 NO(g) 211 H2O(g) 189
To calculate the entropy change, use Delta S = sum of products - sum of reacta...

Answered by • Chemistry tutor

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Draw and explain the atomic structure of one atom of Chlorine.

The answer would include a dot-and-cross diagram, displaying at the centre, a nucleus/the chemical symbol for chlorine, followed by three electron shells, the first containing two electrons, the second ei...

Answered by Maya C. • Chemistry tutor

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Why do simple covalent molecules compounds have low melting and boiling points?

Define:A simple covalent compound consists of a small number of non-metal elements covalently bonded together. (1)For example, H2O , CO2, O2. (1)Relate to MP/BP: The small molecules have only weak intermo...

Answered by Sam B. • Chemistry tutor

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