Term 2/3 End of Topic- Elements, Compounds and Mixtures Flashcards
What are the 3 subatomic particles which make up atoms?
Protons, Neutrons and Electrons
Protons are…
Equal to electrons and the atomic number; located in the nucleus of the atom
Neutrons are…
Atomic Mass- Protons (or atomic number or protons) the only exception being hydrogen with no neutrons and 1 proton; found in the nucleus of the atom
Electrons are…
Equal to protons and the atomic number; found in a shell like configuration orbiting the atom
Electron Config
The first shell can only hold 2, then the rest can hold 8 each, try to start from the right if you have a remainder of electrons.
E.g. If an atom has an atomic number of 9, it has an electronic configuration of 2,7
Atomic number and mass:
Atomic mass is the higher number in position as well as always the higher value in number (except for Hydrogen)
Groups
THE COLUMNS (of periodic table)
Periods
THE ROWS (of the periodic table)
The nucleus is…
Quite small compared to the whole atom
Element
A substance which can not be broken down into anything simpler; made of only one type of atom. Can exist as single atoms e.g. Na, or bonded with other atoms to form molecules e.g. Na2
Compound
Contains 2 or more elements which have been chemically bonded. Elements in a compound are in a fixed ratio which is shown by the formula e.g. water(H20) there are 2 Hydrogen atoms for every oxygen atom. Are difficult to separate and must undergo chemical change for the preceding to happen
Mixture
2 or more elements or compounds in a variable ratio that are not chemically bonded. Easier to separate than Compounds
Example of word equation
Iron + Sulfur (an arrow pointing right would be here) Iron Sulfide
Group 2 metals: Acid + Metal
Salt + Hydrogen
Group 2 metals: Acid+ Metal Carbonate
Salt + Water + Carbon Dioxide