Thursday, June 11, 2009

Why is the ocean getting saltier?

An experiment and explanation by Mark-9
We have been learning about the oceans in science and one of the experiments in out textbook was to try and see if we could figure out why the oceans are getting saltier. Mark did a great job, doing the experiment on his own, and coming up with a great result.
First we needed 1 cup of water
next, totally dissolve 1/4 cup salt into the water.
stir until it is ALL dissolved
It is dissolved
Put the dissolved salt water on the stove and turn it onto high. Bring it to a boil.
keep boiling and boiling until the water is gone---look what is left!!! Salt!!!!
(we couldn't get all the water to evaporate, mom thought it would start to burn and get stinky)
WOW!! The water is GONE, but the salt is BACK.
Measure how much salt is left in the pan. We had more than the 1/4 cup we started with, but mom says that is because all the water was not out of it.
It was a very cool experiment. (Actually it was hot, but I didn't get burned)
What I learned:
The water evaporates from the ocean, leaving the salt and minerals behind. This makes the ocean saltier. Everyday, more water from rivers flows into the ocean and the river picks up salt and minerals from the rocks in the rivers--this makes more salt in the ocean.

1 comment:

Rhonda said...

Yep, I remember Melanie doing this one. Very cool!