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Describe how a buffer solution based on hydrochloric acid can act as a buffer. (5)

HCl ⇌ H++ Cl- (1)Added alkali: H⁺ reacts with added alkali/OH^-(1) Equilibrium shifts right forming Cl^- or H⁺(1) Added acid: Cl<...

Answered by Daisy R. • Chemistry tutor

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Outline the concept of eustatic and isostatic sea level change

Eustatic change refers to a global change in sea level due to an actual rise or fall in sea level. As global temperatures rise due to global warming more precipitation falls as rain and more ice melts fro...

Answered by • Geography tutor

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Explain what the rate-determining step in a reaction is with reference to activation energy.

The rate determining step is the slowest step in a multi-step reaction, and it is the step in the reaction with the highest activation energy. It is the step in the reaction which decides the overall rate...

Answered by Sammy A. • Chemistry tutor

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Outline how light intensity affects the rate of photosynthesis, with reference to the Calvin cycle and effects on the concentrations of GP, GALP and RuBP.

Light is needed to provide energy for the light dependent reactions of photosynthesis. A greater light intensity will provide more energy for these reactions to occur. At a low light intensity, the produc...

Answered by Sammy A. • Biology tutor

8976 Views

What is the difference between the primary and secondary immune responses? (May be asked in the form of how to interpret a commonly used graph on the subject)

In a primary immune response the active immune system must first recognise the pathogen via B-lymphocyte cells with antibodies on their surface that are complementary to the antigens of the invading path...

Answered by • Biology tutor

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