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Calculate the pH of the following solutions: 0.002 mol/dm^-3 KOH

pH by definition is given as -log₁₀(c_H+) or log₁₀(1/c_H+), where c_H+ is the concentration of the H+ ions in the solution.Similarly, pOH= -log₁₀

Answered by Csaba B. • Chemistry tutor

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Why do transition metals form coloured compounds?

Transition elements have 3d orbitals with the same energy level however when molecules/ligands form dative covalent bonds with a metal ion, the electron repulsion causes the 3d orbitals to split into lowe...

Answered by Chiamaka C. • Chemistry tutor

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The reaction for the Haber process is shown below. N2(g) + 3H2(g) ⇌ 2NH3(g) What will be the effect of increasing the pressure on the amount of ammonia present at equilibrium? [1 mark]

Increase.
This question is looking at a reversible reaction - the reaction can occur both forwards and backwards.
Firstly to answer this question you need to appreciate that in a closed reacti...

Answered by Rebecca V. • Chemistry tutor

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Identify which 2 of the following processes involve an exothermic change: melting, boiling, freezing, deposition and sublimation

An exothermic reaction involves an output of heat, so heat is lost overall. This would mean that boiling and melting are definitely not exothermic as they involving putting in heat. Free...

Answered by Ellen S. • Chemistry tutor

6351 Views

What is the easiest way to calculate E cell values?

This is a calculation which students often find tricky. One fail-safe method for doing this calculation is considering E cell = E (reduced) - E(Oxidised). A more positive electrode potential means that a ...

Answered by Rajinder D. • Chemistry tutor

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