Chemistry (Atoms) Flashcards
Structure of Atom
Proton, Electron and Neutron
Size of Atom?
About 0.1nm (nanometres) or 0.0000000001metres (1x10^-10m)
Structure of Atom
Positively charged nucleus that is very small surrounded by a cloud of negatively charged electrons.
(Elements) Mendeleev
Dmitri Mendeleev (1836- 1907)
Arranged elements by chemical properties:
- Space was left for the elements that was unknow at the time.
- Predicted detailed properties for elements as yet unknow:
- Sc, Ga, Ge
- By 1886, the elements has been discovered. The properties were similar to what he had predicted.
Standard electronic configuration
The type of orbital and the energy levels are written first and then the number of electrons are present which is in the orbital and this is written in superscript.
What is atomic mass?
Atomic mass is the total mass of particles of matter in an atom.
What is Atomic Number?
Atomic number is the number of protons in a nucleus.
What is Isotope?
Isotope are the same element with a different mass number. Isotopes have different numbers of neutrons.
Change of State (State of the matter) The four known states of the matter:
- Solid
- Liquid
- Gas
- Plasma
State of Matter
The main difference in the structure of each state is the densities of the particles. In the state of solid, the particles are packed tightly together which means they are unable to move. Contrary to liquid and gas.
