C1: Atomic Structure And The Periodic Table Flashcards
What are 4 processes of chemical mixture separation?
Filtration, evaporation, distillation, chromatography
History of the atom?
John dalton 1803: particles are small marble like balls that cannot be created destroyed or divided
J.J.Thompson 1897: discovered the electron and developed the plum pudding model where the electrons are spread in a positive mass
Ernest Rutherford (1909): alpha scattering experiment and found the nucleus and electron shells
James Chadwick (193w) : existence of neutrons
What is an isotope?
Atoms of the same element that contain the same number of protons and electrons but a different no of neutrons
Relative atomic mass calculation
(Abundance of isotope A x mass of isotope A) + (abundance of isotope B + mass of isotope B) / 100
How was the early periodic table arranged?
Order of increasing atomic weight and not atomic number
How did Mendeleev arrange the periodic table?
He arranged them vertically in properties of their compounds and horizontally in increasing atomic weight, he then found a pattern that chemically similar atoms fell in the same vertical columns
Why were there gaps in mendeleev’s table?
Some elements didn’t fit , so he left gaps. He realised atoms with the same properties were in the same columns and the gaps are undiscovered elements. He used the properties of their surrounding elements to predict the properties of the undiscovered gaps and added the prefix ‘eka-‘ to the
When metals react what do they form?
Positive ions
How many outer electrons to metals have
1-3
How many outer electrons do non metals have
4-7
What oxides are formed from non metals
Acidic or neutral oxides
Which react with acids usually? Metals or non metals
Metals
Boiling points and properties of metals and non metals
METAL: malleable, lustrous, solid, high mp
NON METAL: dull, different states, flaky, low mp
What group is the noble gases?
Group 0
What does monoatomic mean?
Exist as single atoms
Properties of noble gases
Non metals, monoatomic, inert, colourless gases, low mo and bp
Do melting points and boiling points increase or decrease as you go down group 8? Why?
The mps increase as you go down. This is because as the atoms get larger, their mass gets larger leading to stronger intermolecular forces
What group are the alkali metals?
Group 1
What do the alkali metals from when they react with water
Alkaline solutions
Properties of alkali metals
Soft metals, low density, low mp, reactive
Do melting points decrease or increase as you go down group 1?
Decrease
Why does the reactivity increase as you go down group 1?
The electron gets further away and less attract3 to to the nucleus and more easily lost
Metal + water?
Metal hydroxide + hydrogen
Lithium and water reaction observation
Slow reaction, fizzing, moves on surface
Sodium and water reaction observation
Vigorous fizzing, moves rapidly in surface, dissolves quickly
Potassium and water reaction observation
Vigorous, lilac flame, dissolves quick, moves rapidly on surface
Metal + oxygen?
Metal oxide
Metal + chlorine?
Metal chloride
What does diatomic mean?
They form molecules in pairs
What do halogens form when they react?
1- ions (halide ions)
Properties of halogens
Diatomic, poisonous, non metals,
Do the halogen increase or decrease in boiling points as you go down? Why?
Increase (increase intermolecular forces)
What is the appearance of fluorine at room temperature?
Yellow gas
What is the appearance of chlorine at room temperature?
Pale yellow / green gas
What is the appearance of bromine at room temperature?
Red brown liquid
What is the appearance of
iodine at room temperature?
Grey solid
Properties of the transition metals
Lustrous, conductors, high melting points, dense, more than one oxidation state
Why do transition metals produce different coloured compounds?
Ions
Uses of transition metals?
Surgical tools, catalysts, industrial uses
Differences between transition metals and alkali metals?
Transition metals are stronger, denser with higher melting points and less reactive
What is produced when a halogen reacts with
