5 Written Questions
5 Matching Questions
- Strong Nuclear Force
- Plum Pudding Model of the atom
- Atomic Number
- a a powerful force of attraction that binds protons and neutrons together in the nuleus
- b atoms are balls of positively charged material with negative electrons scattered throught
- c the amount of a substance that contains as many particles as there are atoms in exactly 12 g of carbon-12
- d negatively charged particles found outside the nucleus
- e The number of protons in the nucleus of an atom.
5 Multiple Choice Questions
- 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
- from his gold foil expirments, he knew some substances give off + charged particles called alpha particles, most of the mass of an atom is in the nucleus, he reasoned that electrons in the atom are whirled around outside the nucleus, most of the atom is empty space
- a mass of an atom expressed in relation to the defined standard of 12 amu (1 carbon atom)
- 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.
- Uses a needle-like probe to measure differences in voltage caused by electrons that leak, or tunnel, from the surface of the object being viewed
5 True/False Questions
Law of Multiple Proportions → 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
Law of Conservation of Mass → the weighted average of the atomic masses of the naturally occurring isotopes of an element
J J Thompson → 1897- Idea of a subatomic negatively charged particle (electron). Made Plum Pudding model of the atom.
Isotope → a subatomic particle that has a positive charge and that is found in the nucleus of an atom
Neutron → negatively charged particles found outside the nucleus