2006-10-29 12:42:12 · 5 answers · asked by beegiia 1 in Science & Mathematics ➔ Chemistry
Definitively, when new substances appear that weren't there before. Read the first paragraph of the link below to learn more.
Other physical changes, such as heat evolutio or absorbtion, or color changes are not always indicative of a reaction.
2006-10-29 12:46:10 · answer #1 · answered by Favoured 5 · 0⤊ 0⤋
In a chemical change, a new substance appears. Indicators can be a precipitate or color change and many others. In a physical change, the substance just changes it's state like if it changes into a gas, solid, liquid, or broken into pieces.
2006-10-29 21:01:46 · answer #2 · answered by Nerdybones 2 · 0⤊ 0⤋
wen you feel the reaction.or wen you see the reaction
2006-10-29 20:49:37 · answer #3 · answered by THE MOTHERFUCKING PRINCESS 2 · 0⤊ 1⤋
the formula changes colors and/or there is another substance
2006-10-29 20:51:13 · answer #4 · answered by Glendy 1 · 0⤊ 0⤋
It bubbles!
2006-10-29 20:48:02 · answer #5 · answered by cheezzznitz 5 · 0⤊ 1⤋