Tables are a convenient way of recording data. Nevertheless they do follow certain conventions.
The results of an investigation on the effect of light on the cyclosis of chloroplasts
Title of each variable at the top of each column
Units of measurement after a diagonal line, the “solidus”. Note the degrees of precision of the instrument.
Light intensity Distance moved / lx / µm ± 0.1µm 1200 12.5 1500 12.5 1900 25.0 2000 25.0 2500 25.0
Independent variables in the first column arranged in ascending order
Time taken / s ± 0.1s 6.1 3.7 7.3 7.3 7.0
Speed / µm s ± 0.1µms-1 2.1 3.4 3.4 3.4 3.6
Dependent variables in succeeding columns
The data can even be processed in the table
Pure dimensionless numbers with decimal points in line. All to the same number of significant figures
Degrees of precision • Apply a simple rule. The degree of precision is equal to the smallest graduation on the instrument. • You may need to estimate the degree of precision sometimes especially with stop watches. Digital stop watches are said to be accurate to 0.01s but your reaction time is only 0.1s. • For electronic probes you may have to go to the manufacturers specifications (on their web site or in the instructions manual. • Some instruments have not degrees of precision because their reading is relative. Tables can be arranged horizontally too, to save space
The result of pig red blood cells exposed to different salt concentrations
Salt concentration / % ± 0.1% Colorimeter reading / % transmission 0 0.1 0.3 0.5 0.7 0.9 2.0 10.0
MORE COMPLEX TABLES
Give your table a title which concisely states what the experiment is about.
The rate of uptake of water by a leafy shoot under different conditions
……dependent variable next Independent variable first………………… Titles of variables at the top of each column.
Use the « solidus » to separate the title from the units