lesson 2

Question 1

element

Answer 1

a pure substance that cannot be broken down into any simpler substances

Question 2

compound

Answer 2

any substance that is formed by chemical combination of two or more elements and acts like a single substance

Question 3

atom

Answer 3

the smallest unit of an element that retains the properties of that element

Question 4

proton

Answer 4

A stable subatomic particle occurring in all atomic nuclei with a positive electric charge equal in magnitude to that of an electron, but of opposite sign

Question 5

neutron

Answer 5

A subatomic particle with about the same mass of a proton but without an electric charge present in all atomic nuclei except those of ordinary hydrogen.

Question 6

electron

Answer 6

A stable subatomic particle with a negative electrical charge found in all atoms and acts as a primary carrier of electricity in solids.

Question 7

nucleus

Answer 7

the central and most important part of an object, movement, or group, forming the basis for its activity and growth.

Question 8

molecule

Answer 8

a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.