Background Information about Investigation
The rates of chemical reactions in industry are carefully controlled because ‘Time is money!’ So it is important that chemists can make reactions happen and make useful products as quickly as possible. However, sometimes chemists deliberately slow down reactions to avoid health and safety risks. Some reactions can go out of control and lead to large amounts of toxic or flammable gases being made too quickly. One chemical that is made industrially is sodium thiosulfate. Sodium thiosulfate solution is sold in a range of concentrations. Dilute solutions of sodium thiosulfate can be used for cleaning contact lenses and used as a medicine for some cancer patients. Concentrated solutions are used to treat spillages of some chemicals. Sodium thiosulfate is safe to handle and store, but if it is mixed with an acid, a reaction happens. When dilute sodium thiosulfate is mixed with an acid, solid sulphur is made, which makes the solution appear cloudy. The reaction also makes small amounts of toxic sulphur dioxide gas. You will choose one factor and investigate this factor’s effect on the rate of reaction between sodium thiosulfate and dilute hydrochloric acid.
A colorimeter is a device used in colorimetry that generally refers to the device that measures the absorbance of particular wavelengths of light by a specific solution. The output from a colorimeter can be shown by an analogue or digital meter and may be shown as transmittance (a linear scale from 0-100%) or as absorbance (a scale from zero to infinity). The useful range of the absorbance scale is from 0-2 but it is desirable to keep within the range 0-1 because, above 1, the results become unreliable due to scattering of light. In addition, the output may be sent to a chart recorder, data logger, or computer. Rb- Confidence in my hypothesis
In my experiment I didn’t
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