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How do I calculate molar concentrations and determine the mole value based on the mass of a compound?

Molar concentrations are calculated with the basic formula: Concentration (mol/ml) = Number of moles (mol) / Volume (ml). Remember to keep all units consistent and convert when appropriate.

The num...

Answered by Khashayar K. • Science tutor

6460 Views

Please show, using a diagram with explanation, the effect on the UK market for t-shirts of a flood in Bangladesh, a leading cotton growing nation.

Student should realise that the flood will reduce global supply of cotton, causing the supply curve on the diagram to shift left. The market equilibrium will therefore move along the demand curve until th...

Answered by Marshall M. • Economics tutor

2003 Views

Shampoo is sold in two sizes. 1) 500 ml for £1.98 2) 3 litres for £12.80 (now 15% off). Which is better value for money?

Firstly we need to work out the new price of the 3 litres of shampoo after 15% has been taken off. Let's use the three step method for percentages. 100% is £12.80 £12.80/ 100= £0.128 1% is £0.128 £0....

Answered by Francesca N. • Maths tutor

4627 Views

Originally there was only one species of finch (bird) in the Galapagos Islands. However there are now 14 different species of finch in the Galapagos Islands. Suggest an explanation for the development of the 14 different species.

The populations of finches became separated geographically (on different islands). Then genetic variation developed in these isolated communities. Natural selection acted differently in these isolated com...

Answered by Francesca N. • Biology tutor

3842 Views