Which situation describes a chemical change? A. Clay pressed into a mold takes on the shape of the mold.
B. Baking soda added to vinegar gives off carbon dioxide gas.
C. Chocolate changes from a solid to a liquid when heated.
D. Rubbing pencil lead onto paper changes the color of the paper.

0.09 moles of sodium sulfate in 12 ml of solution

What are the major types of a chemical compound

Ammonium perchlorate nh4clo4 is the solid rocket fuel used by the u.s. space shuttle. it reacts with itself to produce nitrogen gas n2 , chlorine gas cl2 , oxygen gas o2 , water h2o , and a great deal of energy. what mass of nitrogen gas is produced by the reaction of 2.1g of ammonium perchlorate?