Matter cannot be created or destroyed "from nothing," but it can change forms. This statement is from which scientific law?

• Newton's Laws of Gravity

• The Law of Conservation of Mass

• The Law of Constant Composition

The fact that each spoonful of pure sugar is always going to contain the same elements, in the same mass proportions is called the law of

• conservation of matter

• composition

• entropy

What electrical charge do protons have?

• they have no charge; they are neutral

• positive charge

• negative charge

What is the name for atoms of the same element with the same number of protons but different numbers of neutrons?

An _____________ is a region of space around the nucleus of an atom where electrons are most likely to be found.

____________electrons are in the highest energy level of an atom.

Draw a diagram of an atom that includes protons, neutrons, and electrons in the correct places.

The number at the top of the B for Boron is called the _______________number. It represents how many _____________the atom has.

• mass, neutrons

• valence, electrons

• atomic, protons

The number below the O for Oxygen is called the _____________number. It represents the total number of_______________ that an atom has in its nucleus.

• mass; protons

• mass; neutrons

• mass; protons and neutrons

_____________are atomic particles that are found inside the nucleus of an atom. These are neutral; they have no charge.