C4.1: Predicting Chemical Reactions Flashcards
What are the group 1 elements known as?
Alkali metals
What can group 1 metals produce when they react with water?
Metal hydroxide
Hydrogen
What are physical properties of alkali metals?
Soft
Low melting points
Good electricity conductors
Alkalis are solid at room temperature
Low densities
Which group 1 elements have the ability to float on water?
Lithium
Sodium
Potassium
What happens to the softness of the metals as you go down the group 1 elements?
Softer as you go down the group
What happens to the softness of the metals as you go down the group 1 elements?
Density increases as you go down the group
What happens to the melting points of the metals as you go down the group 1 elements?
Decreases as you go down the group
How many electrons do group 1 elements have in their outer shells?
1 electron in outer shell
Question: what is produced when sodium reacts with water?
Sodium hydroxide
Hydrogen
What is the reactivity like of lithium in water?
Fizzes steadily and slowly disappears
What is the reactivity like of sodium in water?
Melts to form a silvery ball, fizzes vigorously and quickly disappears
What is the reactivity like of potassium in water?
Immediately ignites, burns with a lilac flame and very quickly disappears
What happens to the electronic structure of group 1 elements when they undergo a reaction?
Atoms lose their outer electron and form cations
The more easily cations form…
The more reactive the metal
What happens to the reactivity as you go down the group 1 elements?
Increases
Why does the reactivity increase as you go down the group 1 elements?
Atoms become larger
Outer electron further from nucleus
Attraction force between nucleus and outer electrons decreases
Outer electron lost more easily
What are the group 7 elements known as?
Halogens
What are physical properties of halogens?
Exist as simple molecules
Exist as diatomic
What colour does chlorine exist in and in which state?
Pale green
Gas
What colour does bromine exist in and in which state?
Brown
Liquid
What colour does iodine exist in and in which state?
Purple black
Solid
What happens to melting and boiling points as you go down group 7 elements? Why?
Increase as you go down the group
More energy needed to overcome the strong intermolecular forces
What happens to density as you go down group 7 elements?
Increases
What happens to reactivity as you go down group 7 elements?
Decreases
What does ‘halogen’ mean?
Salt former
What do halogens produce when they react with metals?
Produce salts
Why is chlorine more reactive than iodine?
Gains electrons more easily than iodine
What is a halide?
A compound containing a group 7 elements when they and one other element which is usually hydrogen or a metal
What can halogens react with in a solution?
Halides
Question: what would chlorine and sodium bromide react to form?
Sodium chloride and bromine
Chlorine DISPLACES bromine from sodium bromide in a displacement reaction
How can you work out if a substance can be displaced or not?
More reactive metals can displace a less reactive metal from its compounds
You can use the periodic table to define which substances are more reactive
What are the group 0 elements referred as?
The noble gases
What is the electronic formation of group 0 elements like?
Complete outer electron shells
No tendancy to lose/gain electrons
Very unreactive
What happens to the boiling points as you go down the group 0 elements?
Increases going down the group - larger atoms - more energy needed to overcome intermolecular forces
What happens to the density as you go down the group 0 elements?
Increases
What are the transition metals?
Placed between group 2 and 3
What are physical properties of the transition metals?
Shiny when freshly cut
Good electric conductors
Strong
Malleable
Often good catalysts
How reactive are transition metals?
Less reactive than alkali metals
React slowly, if at all
Will alkali metals form ionic or covalent compounds?
Ionic
What can you use to test for the present of Group 1 metal ions?
Flame tests
How do rubidium, caesium react in water?
Violent
Tend to explode when they get wet
How can you carry out a displacement reaction?
Measure out a small amount of halide salt solution in a test tube
Add a few drops of halogen solution and gently shake
Colour change - reaction happened and displacement occured. No colour change - no reaction and no displacement
What happens during a reaction between potassium chloride solution (colourless) and chlorine water (colourless)?
No reaction
What happens during a reaction between potassium chloride solution (colourless) and bromine water (orange)?
No reaction
What happens during a reaction between potassium chloride solution (colourless) and iodine water (brown)?
No reaction
What happens during a reaction between potassium bromide solution (colourless) and chlorine water (colourless)?
Orange solution (Br2) formed
What happens during a reaction between potassium bromide solution (colourless) and bromine water (orange)?
No reaction
What happens during a reaction between potassium bromide solution (colourless) and iodine water (brown)?
No reaction
What happens during a reaction between potassium iodide solution (colourless) and chlorine water (colourless)?
Brown solution (I2) formed
What happens during a reaction between potassium iodide solution (colourless) and bromine water (orange)?
Brown solution
I2
What happens during a reaction between potassium iodide solution (colourless) and iodine water (brown)?
No reaction
What is the colour of transition metals like?
Very colourful
