Periodic Table Flashcards
What does the period of an element show?
How many electron shells the element has.
What does the group of an element show?
How many electrons are in the outer shell of the element.
Explain the drop in first ionisation energy across period 2 between nitrogen and oxygen.
The outer electron in oxygen is paired and so is easier to remove due to the repulsion between the two electrons. It is in a less stable configuration compaired to nitrogen.
What is the trend in electronegativity along a period?
Increases as atomic radius decreases and the number of protons increase as the distance between the nucleus and bonding pair of electrons decreases and thus attraction increases and the atom experiences a bigger pull.
What is the trend in electronegativity down a group?
Decreases as atomic radius increases and attraction between the nucleus and bonding pair of electrons decreases. Sheilding increases also and ao the atom experiences less pull on the electrons.
What is the most elecronegative group?
Group 7 and they form +1 anions
Explain melting and boiling point along a period
Group 1-4> Group 5-0
Explain melting and boiling point down a group
Decrease down group 1
Increase down group 7 as the strenght of van der waals froces increases
What is the trend in solubility of group 1 compounds?
Group 1 salts are all soluble in water
What is the trend in solubility of group 2 compounds?
Down the group: Group 2 hydroxides increase in solubility, Group 2 sulphates decrease in solubility
Group 2 carbonates are all insoluble
Group 2 Nitrates are all soluble
NOTE:Magnesium hydrocide and Barium sulphate are insoluble.
What is the trend in solubility of group 7 compounds?
More soluble in organic solvents then polar solvents.
Explain the reactivity of S-Block elements
Increase in reactivity down the group as the atomic radius increases, sheilding increases and nuclear attraction decreases.
Group 1> Group 2
Explain the reactivity of group 7 elements
Decrease in reactivity down the group due a decrease in oxidising power meaning the atom is less able to attract electrons.
What is the trend in thermal stability of group 1 and 2 compounds?
Down the group: Group 1/2 nitrates, carbonates and hydroxides increase in thermal stability due to an atomic radius increase whilst charge remains the same. Thus charge density decreases and require more energy to break down.
When an alkali metal reacts with oxygen what is oxidised and what is reduced?
Alkali Metal is oxidised
Oxygen is reduced
What are the observations of a flame test for group 1?
Lithium= Red
Sodium= Yellow
Potassium= Lilac
Rubidium= Reddish/violet
Caesium= Blue/Violet
What are the observations of a flame test for group 2?
Magnesium= Bright White Light
Calcium= Brick Red
Strontium=Red
Barium= Apple Green
What gas is produced when alkali metals react with water?
Hydrogen
When an alkali metal reacts with water what is oxidised and what is reduced?
Alkali Metal is oxidised
Oxygen is reduced
What are the observations for the reaction of water and group 1 metals?
Lithium-Floats, fizzes steadily, disappears
Sodium- sphere shape, moves quickly on surface, fizzes rapidly, disappears
Potassium- Moves rapidly on water, slef ignites with a lilac flame, small explosion, H2 produced
Rubidium- Violently burns, exploded, disappears
Caesium- Instantaneous explosion
What are the observations for the reaction of water and group 2 metals?
Magnesium- reacts slwoly with liquid water but quickly with steam to form an oxide
Calcium- vigorous, bubbling of hydrogen, white precipitate
Strontium- sinks, bubbles on metal
Barium- vigorously produces hydrogen bubbles, white precipitate
What are the uses of group 2 compounds?
Calcium Hydroxide-Neutralise soils
Magnesium hydroxide-indigestion tablets
Calcium Phosphate-Component of bone and skeletal structures
Calcium ions-msucle operation
Magnesium ions-chlorophyll
Barium sulphate-Medical tracer
How to test for sulphate ions?
Barium chloride reacts with sulphate ions forming a white precipitate
When an halogen reacts witha metal what is oxidised and what is reduced?
Metal is oxidised
Halogen is reduced
