5 Written questions
5 Matching questions
- Nuclear Model of the atom
- Law of Multiple Proportions
- Atomic Number
- James Chadwick
- Mass number
- a the sum of the numbers of protons and neutrons in the nucleus of an atom
- b if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers
- c The number of protons in the nucleus of an atom.
- d created by Ernest Rutherford. Replaced the Plum Pudding Model. Atom is like a miniature solar system with the positive particles in the middle and the negative particles orbiting as the planets do around the center.
- e confirmed the existence of the neutron
5 Multiple choice questions
- 1897- Idea of a subatomic negatively charged particle (electron). Made Plum Pudding model of the atom.
- a subatomic particle that has no charge and that is found in the nucleus of an atom
- the tiny, dense central portion of an atom, composed of protons and neutrons
- Conducted by Ernest Rutherford in which alpha particles that were shot at gold foil were deflected when they hit the positive center of gold atoms. The nucleus was discovered as a result of this experiment.
- 1700s-1800s 1. elements are composed of tiny indivisible perticles called atoms 2. atoms of the same element are the same, and atoms of different elements are different 3. atoms can chemically combine in simple whole number ratiosto form compounds 4. chemical reactions occur when atoms are separated, joined or rearranged
5 True/False questions
Law of Conservation of Mass → the law that states that mass cannot be created or destroyed in ordinary chemical and physical changes
Cathode-ray-tube → evacuated glass tube in which a stream of electrons emitted by a cathode strikes a fluorescent material, causing it to glow(used to discover the electron)
Law of Definite Proportions → the fact that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound
Mole → the amount of a substance that contains as many particles as there are atoms in exactly 12 g of carbon-12
Average Atomic Mass → a mass of an atom expressed in relation to the defined standard of 12 amu (1 carbon atom)