The Periodic Table Flashcards
Who was arguably the greatest contributor to the development of the Periodic Table?
Mendeleev
Give four features of the Periodic table developed by Mendeleev
- left gaps
- arranged elements in groups and periods
- separated the metals and non metals
- arranged elements in order of increasing atomic mass
Four ways that the current Periodic table is different to Mendeleev
- No gaps
- Noble gases
- Elements in increasing atomic number
- Actinides and Lanthanides
Why is the fact that Mendeleev left gaps for elements not yet discovered?
This enabled him to predict properties of undiscovered elements
What group are alkaline metals in ?
1
What is the name given to horizontal rows in the Periodic table?
Periods
Explain why the atoms gradually decrease in size across a period
The extra electron going into the same shell and the extra positive charge on the nucleus caused by the extra proton increases the attraction on the shells, pulling them closer to the nucleus.
In which group are the most reactive metals found?
Alkali metals in group 1
Give four properties of metallic elements
Shiny solids
Good conductors or heat
Sonorous solids
Usually malleable and ductile
Give four properties of non metallic elements
Poor conductors of heat
Non-sonorous solids
Can be a gas, solid or a liquid at room temperature
Usually dull
Give four trends of group 1 metals down the group
- Bigger atoms
- Lower melting/boiling point
- More reactive
- Even softer to cut
List four observations of group 1 metals reacting with water
- Metal floats
- Fizzing occurs
- The metal moves about the surface
- The metal disappears with a smoke and crackle/explosion
Why are group 1 metals more reactive descending the group?
The outer electron is further from the nucleus and therefore easier to lose
Why is are group 1 metals stored under oil?
They would react with moisture in the air
What is the test for hydrogen?
Relighting a glowing splint
Explain why all group 1 metals have similar chemical properties
They all have one electron in their outermost shell that when they react forms a positive ion with a stable electronic configuration
Give the appearance of the following elements at room temperature : Fluorine - Chlorine - Bromine - Iodine -
Pale yellow gas
Pale green gas
Red-brown liquid
Dark grey-black solid. Gives purple vapour (iodine sublimes)
Down the group halogens become:
Bigger atoms
Less soluble, although none of the halogens are very soluble
Increasing melting/boiling point
In group 7 reactivity ….. as you go up the group
Increases
Give 5 physical properties of chlorine gas
- Pale green gas
- Heavier (denser than air)
- Toxic
- Slightly soluble in water
- Bleaches damp litmus paper (test for chlorine)
Give three uses of chlorine
- Water sterilisation
- Manufactures of PVC
- Bleach
A more reactive halogen can replace a ….. …… halogen from a solution of its …..
less reactive , salt
Give the observations of the colour changes in the solution when a halogen reacts with a metal halide with the following elements:
Chlorine : KCl - KBr - KI
Bromine : KCl - KBr - KI
Iodine : KCl - KBr - KI
Chlorine: KCl- no reaction
KBr- Solution turns orange (bromine is water produced)
KI- Solution turns brown (iodine in water is produced)
Bromine: KCl- Solution remains orange (no reaction)
KBr- No reaction
KI- Solution turns brown (iodine in water is produced)
Iodine: KCl- Solution remains brown (no reaction)
KBr- Solution remains brown (no reaction)
KI- no reaction
Dissolved in oranges solvents, iodine gives a …… ….. . When iodine is dissolved in …../…. …. ….. it is brown
Purple solution . Ethanol/potassium iodide solution
Give two properties of bromine:
Liquid, red brown
Why are group 0 non- metals unreactive?
Their lack of reactivity is due to each element in the group having a full outer shell of electrons.
Give five properties of transition metals
- they have higher melting points
- high density
- much less reactive with water
- they react and form ions with different charges but group 1 metals only form 1+ ions
- they form coloured compounds
Give the four coloured compounds and their colours formed from transition metals
Copper(ii) oxide - black
Copper(ii) carbonate - green
Hydrated copper(ii) sulfate - blue
Copper (ii) salt solution - blue
How many elements had been discovered in Mendeleev’s time?
63
Mendeleev arranged the elements in increasing atomic weight - how do we arrange them today?
Increasing atomic number
Where are the noble gases found in the Periodic table?
Group 0
Give three properties of all metals
- hard
- shiny
- malleable
Why is a mixture of metals used in coinage
It is stronger and harder than pure metal
Name 2 transition metals used in catalytic converters
Platinum and rhodium
What do the glaze mixtures used in coat clay contain?
Transition metal compounds
What does it mean when an element sublimes?
changes from solid to gas without going through a liquid phase
Name group 2 metals
Alkaline earth metals
Where are the transition metals located ?
Group 2 (Scandium to Zinc)
Observations of lithium in water (3)
- Metal floats
- Fizzing occurs
- Moves about the Surface and disappears with smoke
- Melts into a ball
Observations of sodium in water (4)
- Metal floats
- Fizzing occurs
- Sodium disappears
Observations of potassium in water(4)
- Metal floats
- Fizzing occurs
- Heat is released
- A lilac flame is observed
Properties of alkali metals (5)
- Low density
- First three are less dense than water
- Easily cut
- Shiny when freshly cut
- Tarnish rapidly in air
How to test for chlorine gas
- Damp Universal indicator paper changes to red and then bleaches white
