i had to do a science experiment where i put regular water in 1 beaker and put it under a flame for 10 min, and 1 beaker with salt and put it under a flame for 10 min. I need to know what type f changes occured during the lab. Idk if it was a chemical change or physical change or whatever, just please help!!!
2006-10-21 13:25:51 · 3 answers · asked by Rosey Cole 1 in Science & Mathematics ➔ Chemistry
Basically it would be just phase changes, not chemical changes. In both cases the heat entering the water would be increasing the rate of evaporation (that is, from liquid to gaseous phase) and with the salt, there would also be a phase change from solid crystalline sodium chloride to aqueous (i.e. dissolved) sodium and chlorine ions.
2006-10-21 13:32:31 · answer #1 · answered by poorcocoboiboi 6 · 0⤊ 0⤋
You started with water and saltwater. You ended with water, saltwater and steam. Steam is still water, in the vapor phase. No chemical change, so physical changes only. Also, salt doesn't even melt at the temperature water boils. The saltwater beaker ended with the same amount of salt, but less water, making it saltier.
One other thing that might come up--saltwater boils at a higher temperature and freezes at a lower temperature than regular water. The salt ions at the water's surface interfere with the water molecules trying to escape, so you have to put more energy into saltwater to get it to boil. They also interfere with water molecules trying to crystallize, so more energy has to be taken out to get it to freeze.
2006-10-21 13:46:26 · answer #2 · answered by Valerie R 2 · 0⤊ 0⤋
Hi. Just right down what you saw. The salt dissolved, some vapor formed, some water condensed on the side of the beaker... everything you saw.
2006-10-21 13:31:04 · answer #3 · answered by Cirric 7 · 0⤊ 0⤋