SC3 - Atomic Structure ✓ Flashcards
SC3a - Name the three base rules of atomic theory.
- All matter is made up of atoms
- Atoms cannot be broken down into smaller parts
- Atoms cannot be created or destroyed
SC3a - Names the three subatomic particles as well as their relative mass and charge.
- Protons:
- M: 1
- C +1
- Neutron:
- M: 1
- C Neutral (0)
- Electron:
- M: 1/1835 (negligible)
- C -1
SC3a - Describe the structure of an atom
- Protons and neutrons centred in a nucleus.
- Electrons orbiting outside in electron shells.
SC3b - What did the Rutherford Gold foil test reveal about the space inside atoms?
Atoms are mostly empty spcae
SC3b - What is an atomic number?
The number of protons in an atom. the bottom number on the symbol for an element
SC3b - What is a mass number?
- The number of protons + neutrons in an atom (the mass).
- The top number on the symbol for an element.
SC3c - What is an isotope?
Two atoms (of the same element) with the same atomic number but different mass numbers (amounts of neutrons)
SC3c - What does the symbol Ar stand for and what does it mean?
- Relative Atomic Mass.
- The average mass of the naturally occurring form(s) of an element in relation to a Carbon-12 atom
SC3c - How do you calculate the Ar of an element from the abundance of its isotopes.
(M1 x A1) + (M2 x A2) (etc.) ÷ 100 (M=Mass A=Abundance)
SC3c - Why does chlorine have a mass number with a decimal?
- It is its relative mass.
- There are two isotopes of chlorine, 35 and 37.
- Chlorine - 35 is more abundant than 37.