C1 - Atomic Structure Flashcards
What are atoms?
- They’re really tiny.
- All substances are made up of atoms.
What are atoms made up of?
Protons, neutrons and electrons.
What is the nucleus of an atom?
- The middle.
- Contains protons and neutrons.
- Positive charge because of the protons.
- Almost the whole mass of the nucleus of the atom is concentrated.
What are electrons?
- Move around the nucleus in electron cells.
- Negative charge
- Cover a lot of space.
- Virtually no mass. (0)
Proton Number = Electron Number
- Atoms are neutral - they have no charge.
- Proton number is the same as electron number.
- In an ion, protons != electrons. Means it hasn’t got overall charge.
- An ion with a 2- charge, has too more electrons than protons.
Atomic Number and Mass Number
Nuclear symbol shows you its proton number and its mass number.
Bottom Number = amount of protons.
Mass number = Protons and neutrons in nucleus.
Neutrons = Mass Number - Proton Number
Elements
Substance made up of atoms that all have the same number of protons in their nucleus.
Why do elements consist of atoms with the same atomic number?
Its the number of protons in the nucleus that decides what tupe of atoms it is.
An atom w/ 1 proton in its nucleus = hydrogen.
How can atoms be represented?
Atoms can be represented by symbols.
1 or 2 letter symbols (C = Carbon) (Na = Sodium)
What are isotopes?
Different forms of the same element.
Same atomic number, different mass number.
Carbon 12 = 6P, 6E, 6N // 12M-6P = 6N
What is an abundance?
Amount of all the isotopes that make up the element.
Relative Atomic Mass Formulae
Sum of (isotopic abundance X Isotopic mass number) / sum of abundance of all the isotopes.
Relative Atomic Mass of Cu-63 and Cu-65
(69.2x63) + (30.8x65) / 69.2 + 30.8 = 4359.6 + 2002 / 100 = 6361.6 / 100 = 63.616 = 63.6
