2H2 + O2 = 2H2O If 120 grams of oxygen (O2) react with an excess of hydrogen, what mass of
water (H20) will be formed?

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.

Write and balance the chemical equation that represents the reaction of aqueous sulfuric acid with aqueous sodium hydroxide to form water and sodium sulfate. include phases.

What is the most common reason for matter changing its state?