osmosis
visitors this year: 77 A pressure sensor can be used to monitor the progress of osmosis. In this experiment a dialysis bag containing sucrose solution is placed in a beaker of water. Over a...
energy in food
As food burns it releases energy. This energy can be used to heat up a known volume of water and so calculate its energy content. The temperature change can be easily monitored using a temperature sensor. Furthermore, if the food stops burning too soon, the graph will show how much the water cools and you can add this temperature change into your calculations.
respiration; germination; fermentation; anaerobic & aerobic
When living things respire they use up oxygen. This can be monitored using an oxygen sensor. The living thing can be a plant, animal or microorganism. Maggots, locusts, or yeast are often used and so can pond-weed. If you use Elodea, its container should be kept in the dark or wrapped in foil.
It is also quite easy to show how temperature affects the rate of respiration
– however, in this example, the oxygen sensor should be able to compensate for its own response to temperature changes.
photosynthesis – measure oxygen or pH
Sensors can be used to monitor photosynthesis. They can show that as the light level increases, the oxygen level will also increase. It is also possible to show the effect of carbon dioxide levels (as added hydrogen carbonate solution) and to show the effect of coloured light.
enzymes: starch & amylase; pepsin & protein
Two experiments: in one amylase catalyses the hydrolysis of starch. Iodine can be used as an indicator to show that the starch has been broken down. A light sensor can be used, like a colorimeter, to monitor this change.
Another experiment aims to show the effect of different temperatures on the action of amylase.This experiment studies
the effect of the enzyme pepsin on protein. Pepsin catalyses the hydrolysis of the protein, albumin into amino acids. As the protein solution is cloudy and amino acids are soluble the liquid changes from cloudy to clear. The light sensor can be used, like a colorimeter, to monitor this change.
temperature sensor
visitors this year: 148 Sensors to measure heat and temperature These sensors are available in all flavours to suit different applications. You should be able to decide on the type that suits whole class...
a data logger is a scientist’s camera
visitors this year: 127 data loggers – the scientist’s camera! There is a rich world of data waiting to be collected. Take an accelerometer with you on a theme park roller coaster or if...
stopping sound / large & small ears
visitors this year: 91 photo credit: unsplash-logoJoanna Kosinska
