Topic 7 - Groups in the periodic table (Year 11) Flashcards
True or False: Group 1 metals are soft?
True - all group 1 metals are soft
What are Group 1 metals called?
Alkali Metals
Why are elemets placed in group 1?
They have similar chemical properties ad electronic configuration
Why do elemets in group 1 share similar chemical properties?
Group 1 elemets all have one electron in their outer shell, so they react in similar ways
A piece of sodium is added to some cold water. A reaction takes place. What are the 2 products?
Sodium Hydroxide and Hydrogen
Give the balaced equation for the reaction between lithium and water
2Li + 2H2O → 2LiOH + H2
Describe what you would observe during the reaction between potassium and water.
Potassium will fizz around the surface of the water and melt in the heat of the reactio. It will also get hot enough to ignite the hydrogen gas produced. There would be a lilac flame given off.
How would you expect the reaction between rubidium and water compare to the reaction between potassium and water?
Rubidium is more reactive than potassium so it will react more violently with water than potassium. Rubidium will more than likely explode durig the reaction with water.
What happens to reactivity as you go dow group 1?
As you go down group 1 reactivity increases
What happens to the melting and boling points as you go down group 1?
Melting and boiling points decrease as you go down the group.
Explain why the reactivity of the group 1 metals increases as you go down the group
As you go down the group, the atoms gain an extra electron shell. This shell means the atoms get bigger, there outer electron is further away from the nucleus, so there is less attraction between the nucleus and outer electron (more electron shielding). The means less energy is needed to remove it.
What charge ions do all group 1 metals form?
+1
Why are alkali metals stored under oil?
Alkali metals are stored under oil because they are highly reactive with oxygen.
How would a teacher demostrate the reaction between group 1 metals water?
Fill a water trough with water, place behind a safety screen. Teacher to wear safety glasses, using tweezers grab a small piece of the metal, cut the metal using a scapel, placig the esxcess back into the oil. Remove any excess oil off of the metal and place into the water trough.
What would be the products of the reaction between lithium and oxygen?
Lithium Oxide
Describe the physical appearance of fluorine at room temperature
Yellow gas
Describe the physical appearance of chlorine at room temperature
Green gas
Describe the physical appearance of bromine at room temperature
Brown liquid
Describe the physical appearance of iodine at room temperature
Dark gery/purple solid crystals
Describe the physical appearance of astatine at room temperature
Black solid
What are group 7 also called?
Halogens
What do we call Group 7 ions?
Halide ions
What is the charge on a halide ion?
-1
Describe the trend I reactivity as you go down group 7
Reactivity decreases
Explain why the reactivity decreases as you go down group 7
As you go down the group, the atoms gain an extra electron shell. This shell means the atoms get bigger, there outer electron is further away from the nucleus, so there is less attraction between the nucleus and outer electron (more electron shielding). The means it is harder for the atom to gain the extra electron.
Define: Displacement Reaction
A reaction where a more reactive element takes the place of a less reactive element
A few drops of iodine water are added to potassium chloride, explain why a reaction would not be observed.
There wouldn’t be a reaction due to iodine being less reactive than chlorine.
Adding chlorine water to a solution of sodium bromide results in a colour change. What colour change would be seen
Colourless to a brown/orange colour
Complete the equation for the reaction: potassium iodide + chlorine
Potassium Chloride + Iodine
What happens to the melting and boiling points of group 7 elements as you go down group 7?
The melting and boiling points increase.
Give the balanced equation for the reaction between lithium and chlorine
2Li + Cl2 → 2LiCl
What would be the prodcut if you reacted sodium with iodine
Sodium Iodide
Adding chlorine water to a solution of sodium bromide results in a colour change. What substance is oxidised during this reaction? Which substance is reduced?
The chlorine atoms gain an electron and so are reduced to chloride ions. The bromide ions lose an electron and so are oxidised to bromine atoms.
What is Group 0 also called?
Noble gases
True or false: Boiling point increases as you go down group 0?
True, the further down group 0 you go, the higher the bboiling point.
What is the reactivity of group 0?
Group 0 elements are all unreactive.
Explain why Group 0 are unreactive
Group 0 elements are unreactive due to them having a full outside shell. Because of the full outsidxe shell, they do not need to lose or gain ay electrons.
Define: Inert
Inert means an element is unreactive
Does kryton have a lower or higher boiling point than argon? Explain why.
Krypton has a higher boiling point than argon. This is because as you go down the group, boiling point increases.
Why is a noble gasses like argon used in old fillament lightbulbs?
Argon is used because it is inert. This means when the fillament gets hot it won’t react.
Balloons filled with helium float, Explain why.
Helium is less dese than air. Thos meas the balloon floats.
What happens to density as you go down group 0
Denistry increases due to the size of the atom icreasing.
Chlorine water+ potassium iodide → ?
Potassium chloride + iodine
Alkali metal + water → ?
metal hydroxide + hydrogen
How many outer-electrons do alkali metals have? What does this mean?
- This means that alkali metals are very reactive as are keen to give away their outerelectron and maintain a full outer shell. They then become a positive ion.
Physical properties of alkali metals
Low melting/boiling points in comparison to other metals.
Very soft.
Very reactive.
Dull colored.
Alkali metal + Oxygen →
Metal oxide
Lithium + Oxygen → ?
Lithium Oxide
Alkali Metal + Halogen →
Metal Halide
Potassium + Chlorine → ?
Potassium Chloride
How does an alkali metals period affect its reaction with water?
As you go down group 1, speed and violence of the production of metal hydroxide increases.
What color does the left over solution from alkali metals and water turn universal indicators?
Purple as its an alkaline solution.
What color is the flame when an alkali metal is put in water?
Lilac
What type of molecule are halogens? What are their bonding?
They are diatomic (pais e.g. Cl2) molecules joined by covalent bonds which gives both atoms a full outershell.
Characteristics of bromine
Poisonous, red, brown liquid that gives off an orange vapour at room temperature.
Chlorine characteristics and how do you test for it?
Fairly reactive, poisonous green gas.
It will turn damp blue litmus paper momentarily red (as Cl is acidic) and then bleach it white.
Characteristics of iodine
Dark grey crystalline solid which gives off purple vapor when heated.
What are noble gases used for?
ARGON is used in filament lightbulbs as it provides and inert atmosphere and so will stop the v hot filament from burning up in the air.
The same principle is used in camera bulbs with argon, krypton and xenon to stop the flash filament from burning up in high temp flashes.
ARGON and HELIUM can be used to protect metals that are being welded as it stops the hot metal from reacting with the oxygen.
HELIUM is used in airships and party balloons as He has a lower density than air which makes the balloon float, it’s also nonflammable so is safer to use than hydrogen.
