Search our library of Chemistry questions

Top answers

Chemistry

All levels

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

1508 Views

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

2006 Views

When propanal is reacted with potassium cyanide under weakly acidic conditions the resulting mixture does not rotate plane polarised light. Explain this observation.

A common mistake is to answer this question with the explanation that the light is not rotated because no optical isomers are present. However, this is incorrect. The only other time where plane polarised...

Answered by Sally D. • Chemistry tutor

4064 Views

What's the difference between Bronsted-Lowry acids and Lewis acids?

A Bronsted-Lowry acid is a proton donor. (Bronsted-Lowry acids and bases only involve protons or H+)A Lewis acid is an electron pair acceptor. (Lewis acids and bases involve the transfer of electrons, a b...

Answered by • Chemistry tutor

1920 Views

Calculated the Relative Molecular Mass of calcium (II) chloride using the periodic table.

Calcium (II) has a charge of 2+ and each chloride has a -1 charge giving a formula of CaCl2 when balancing the charges out. Ca (Relative Atomic Mass) = 40.08 and Cl (Relative Atomic Mass) = 35.45So Relati...

Answered by Gabriel L. • Chemistry tutor

6366 Views