Elements, Atomic Structure, Compounds And Mixtures Flashcards
Define compound
Two or more elements chemically bonded in a fixed ratio
Define mixture
A substance with two or more elements OR compounds in a variable ration and are not chemically bonded
Define element
A substance made of 1 type of atom
Define malleability
The ability to be bend into different shapes
Define ductility
The ability to be stretched into wires
What is the relative mass and relative charge of a proton?
Relative mass: 1
Relative charge: +1
What is the relative mass and relative charge of a neutron?
Relative mass: 1
Relative charge: 0
What is the relative mass and relative charge of a electron?
Relative mass: 1/1840
Relative charge: -1
What two particles make up the nucleus?
Protons and neutrons
What is the atomic number?
Number of protons in an atom
Is the bottom number
What is the mass number?
The number of protons and neutrons
Is the top number
What was John Dalton’s idea of atoms?
Atoms are tiny solid balls
- invisible
- atoms of 1 element all the same
- atoms of different elements are different
- compounds are formed by combining atoms
What was J . J. Thomson’s idea of atoms?
Discovered electrons
Believed atom made of smaller things
Created the plum pudding model, with raisins being elections inside a sphere of positively charged pudding
What was Ernest Rutherford’s idea of the atom?
Atom was 99% space
Discovered positive charged nucleus
What was Niels Bohr’s idea of the atom?
Same as Rutherfords, but in 1913 published the idea of electron shells
What was James Chadwicks idea of atoms?
Discovered neutrons in nucleus
Define Isotopes
Atoms of the same element with same number of protons, but with a different number of neutrons
How to calculate relative atomic mass?
(RAM 1 × %) + (RAM 2 x %)
Divided by
100
How many electrons can the first energy level/shell hold?
2
How many electrons can the second (and further) energy level/shell hold?
8
Define group
Vertical column of elements
Define period
Horizontal row of elements
How is an atom charged if it loses an electron?
Positively/+1
How is an atom charged if it gains an electron?
Negatively/-1
