Chemical Reactions and Conservation of Mass
A chemical reaction is a process where substances change into new substances with different properties. Wood burning, iron rusting, and baking a cake all involve chemical reactions. A key rule governs all of them — the law of conservation of mass — and it shows up on the test again and again. GED Science Complete […]
States of Matter and Changes
Water can be ice, liquid, or steam — the same substance in three different forms. These forms are the states of matter, and the changes between them are driven by heat. This is a common, approachable test topic, and it comes down to how tightly the particles are packed and how much energy they have. […]
