In this Activity, students measure the rate of warming for a chilled thermometer bulb held in room temperature air, for a chilled bulb held between two fingers, and for a few milliliters of ice-cold water. Students discover that the warming process is not linear. This Activity emphasizes the importance of measuring temperature change and its relevance to other experiments.
In this Activity, students compare the combustion of different substances such as a glowing wooden toothpick and lit birthday candle in air, oxygen, exhaled breath, and carbon dioxide environments. The oxygen and carbon dioxide are generated from supermarket chemicals. This Activity can be used to explore the chemistry of oxygen and combustion.
In this Activity, students observe and compare the behavior of three lightsticks that are exposed to three different temperature ranges (cold, room temperature, and hot). The Activity could be used early in the school year to give students practice in making detailed observations and devising reasonable explanations for those observations. It illustrates the use of qualitative vs.
In this Activity, students observe UV-sensitive beads that have been melted into flat disks, explore the temperature behavior of the disks, and then use the disks to investigate the effectiveness of different sunscreens. The Activity shows applications of chemistry in the real world.
When acidic dichromate and iodide solutions are mixed, no immediate reaction takes place. Addition of iron(II) solution brings about rapid formation of brown triiodide.
An acidified iron(III) solution is added to iodide solution to see if oxidation to triiodide will occur.