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Use the following data to explain why NaCl is soluble in water: ∆H = +31 kJmol-1, S(Na+(aq)) = 320.9 JK-1mol-1, S(Cl-(aq)) = 56.5 JK-1mol-1, S(NaCl(s)) = 72.1 JK-1mol-1 Are there any temperatures at which you would not expect NaCl to dissolve?

This is a nice simple calculation question which explores some basic thermodynamic principles and begins to apply them to simple reactions (in this case, solid salt dissolving in water) allowing predictio...

Answered by Kieran R. • Chemistry tutor

7600 Views

How can one differentiate between the organic compounds propanal (CH3CH2CHO) and propanone (CH3COCH3)?

React a sample of each compound with Tollens reagent. The aldehyde (propanal) will be oxidised to a carboxylic acid (propanooic acid) and will form a silver mirror. No change will be observed with the ket...

Answered by Julie T. • Chemistry tutor

3983 Views

What is the difference between exothermic and endothermic?

Exothermic and Endothermic are opposite reactions. All reactions need energy to be put in to start them off, this is called the activation energy, but th...

Answered by • Chemistry tutor

1885 Views

Why does the structure of lithium oxide allow it to conduct electricity under certain conditions?

Lithium oxide has the formula Li₂O. It has an ionic structure as it is formed from a metal and a non-metal. It has lithium ions with a +1 charge, as lithium is found in Group 1 of the periodic ...

Answered by Amy I. • Chemistry tutor

9505 Views

An industry is producing copper sulphate (CuSO4) from copper carbonate (CuCO3) and sulphuric acid (H2SO4). The company calculated that from 800 g of CuCO3 they will produce 1kg of CuSO4. However they only produced 900g. What is the percentage yield ?

The percentage yield is calculated in the following way: (Actual yield/Theoretical yield)*100 Here, the actual yield is 900g and the theoretical yield that the company calculated is 1kg. ...

Answered by Dora L. • Chemistry tutor

2148 Views