Search our library of Chemistry questions

Top answers

Chemistry

All levels

Why does graphite conduct electericity but diamond does not if both substances have a giant covalent structure?

Graphite consists of carbon atoms joined together. Since carbon has 4 unpaired electrons in it's outer shell, it can form a maximum of 4 covalent bonds by sharing each of it's unpaired electrons with anot...

Answered by Prithi N. • Chemistry tutor

13077 Views

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

7488 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

3897 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

1830 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

9261 Views