HELP ME need info on nitrates 4 sci. fair project

[Bananagirl6495]

Okay so im doing a science fair project on how hot polluted water gets when its exposed to sunlight. one of pollutants is fertilizer which contains nitrates. Now someone told me that that might affect my data, if it does then why? can someone please explain in a way that a 7th grader can undestand

Edited April 30, 2009 by Bananagirl6495
grammer

[hermanntrude]

certain chemicals when added to water can cause the water to heat up or cool down. For instance, if you add sodium hydroxide to water, the water can often boil if you add enough.

[UC]

Hermann has it right. They only affect the temperature when they are dissolving. Ammonium nitrate, for example, gets icy cold when you dissolve it in water. In fact, along with urea, it is used to make instant ice packs.

 

Just make sure you let all the solutions come to room temperature before you start the tests.