Writing half equations and ionic equations Thursday, Jun 7 2007 

Metals davisdag 9:49 am

without having to type equations in this post!! Arrrgggggg

Half equations help us understand the electron transfer process between metals and non-metals. Generally:

* metals lose electrons to form metal ions (cations)

* non metals gain electrons to form non-metal ions (anions)

* hydrogen ions gain electrons to form hydrogen gas.

Using these generalisations, we can write half-equations for the reactions between metals and dilute acids. Half equations must be balanced in terms of atoms and charges.

Ionic equations are created by summing two-half equations so that the number of electrons lost by the metal equals the number gained by the non-metal or hydrogen ion.

Now …….. remember the dot point for this……” construct half equations to represent the electron transfer reactions occurring when metals react with dilute hydrochloric and sulphuric acid”…..in other words you only need to be concerned with half equations associated with metals + Acid………(even though you can do it all reactions of metals 🙂  – you’re such clever chickens!!!!)

Does this help ??? Remember to use that text that holds up the leg of your desk to find some extra examples and questions to practise on………

 

I hear you Lena! Research task advice…… Thursday, Jun 7 2007 

tasks davisdag 9:34 am

Can only offer you my advice regarding the research task. Remember that you will be asked questions on anything that is listed for research……..that is, it could come from either column on the task sheet.

It is really up to you what research you do…………BUT you will find it difficult to answer some types of questions if you don’t deal with all the topics. There is no page restriction on the research task, so as long as you don’t waffle………you should try and develop some succinct notes.

 Good setting out will also mean that you will be able to access your notes efficiently in the task. AND………you will get some marks allocated for following the instructions.

Hope this helps Lena and others…….anything else??