practical+write-up

toc =Introduction=

The aim of this page is to give some ideas as to what should go into your practical write-up. This is written in general terms so you will need to think about your actual work and decide what is needed and what is not needed in your case.

Try to keep your writing in the third person and in past tense...

...so not "I added" or "I put"

.. but try to use "2.0g of Calcium Carbonate (CaCOmedia type="custom" key="5509965") was added to the acid"

=The investigation write-up=

Title
Your investigation should have a title that tells the reader what your experiment is about.

For example

An investigation into the effects of concentration on rates of reaction

Date
You write up should have a date noted of the day **you did your experiment**.

Introduction
This section would explain in more detail what your experiment is about and gives some specifics for your experiment.

For example

This investigation will look at the effects of changing the concentration on the rate of reaction for the reaction of calcium carbonate and hydrochloric acid.

CaCOmedia type="custom" key="5509981"media type="custom" key="5521549" + 2HClmedia type="custom" key="5521551" -> CaClmedia type="custom" key="5509983"media type="custom" key="5521551" + COmedia type="custom" key="5509983"media type="custom" key="5521553" + Hmedia type="custom" key="5509983"Omedia type="custom" key="5521557"

Prediction
You will want to make a prediction.

I think that if I increase the concentration the rate of reaction will increase.

Background
You will then want to justify your prediction with your scientific knowledge. For example in the prediction above you will want to talk about particles and collisions to explain your prediction

Variables
This is very important. In a scientific investigation you will try to change one thing and measure the effect. Everything else will be kept the same. This is called a **fair test.** As you get better you should start using a more advanced vocabulary for this.

Independent Variable
This is the variable that you will change.

In the example I have been using you would be changing the concentration of the acid.

Dependent Variable
This is what you will measure.

In our example this would be the volume of gas produced over time.

Controlled Variables
These are all the other things that could effect your measurements that you will keep the same to make sure you are only seeing the effects of changing you Independent Variable. You should list them all and explain how you will keep them the same. This could be as simple as saying you will use the same amount of a chemical, or that you will make sure all your experiments happen at the same temperature.

Diagram
Your experiment is likely to need a labelled diagram.

In most cases your digram will need to be in two dimensions, drawn with a ruler and a sharp pencil and the labels clearly marked with lines to the correct equipment.

The aim of your diagram is to make sure that whoever reads your write-up could follow your instructions and your diagram and set up the experiment in exactly the same way. But you don't need to assume they are stupid, so you do not need to draw standard equipment such as stopwatches, labcoats and safety glasses.

If you are using a computer for your write up, the same guidelines apply - use two dimensions, use thin lines, use straight lines where possible, try to distinguish between lines of your equipment and lines for your labels. If you use images from the Internet, make sure you reference them and have the right to use them.

Method
This should be a series of step by step instructions of what you did. The amount of detail should be enough for someone to repeat your experiment only using your instructions.

Try to avoid using sentences like:
 * I set up the equipment...

Results
This should be a table of the results that you took. At the top of each colu,n should be a title of what you are measuring an **and the units**

The columns should contain just numbers, with a number of decimal places which shows how accurately you measured.

For example


 * Time||Volume ||
 * s||ml||
 * 30||23||
 * 60||37||

Graph
You might find that your results can be displayed as a graph which shows the trend in the results. You should consider what type of graph best works with your results.

Your graph should be drawn on graph paper with the axes labelled including units, drawn with a sharp pencil and rule and filling the graph paper.

Conclusions
What do your results show you? Do they prove or disprove your prediction? How do they prove or disprove the prediction? What scientific knowledge explains this?

Evaluation
How could you improve your experiment? What did you find hard? What changes could you have made to make it easier for you?