Topic 2 - Ionic Compounds And Analysis Flashcards
What two things make up ionic bonding from the periodic table?
A metal and a non-metal
How many electrons in group one does an element giveaway in ionic bonding?
They give 1 electron away making them positively charged
If an element is in group 6 how many electrons does it gain in ionic bonding?
2 electrons making it negatively charged
Why don’t elements in group 8 react with anything?
Because they have full outer shells
If an element from group 7 and group 2 were to ionic bond how many of each element would you need and why?
2 X Group 7 elements
1 X Group 2 element
This is because a group 2 element gives away 2 electrons and a group 7 element only gains 1 electron, so you would need TWO group 7 elements to ONE group 2 element (2:1)
What type of structure do ionic compounds have?
A giant lattice structure made up of positive and negative ions.
Why in a giant lattice structure are the ions so closely packed together?
Due to the very strong electrostatic forces of attraction between oppositely charged ions
What is ionic bonding?
Ionic bonding occurs between positive and negative irons which attract each other and bind together to form ionic compounds
Why do ionic compounds have high melting and boiling points?
Due to the very strong bonds between ions. It takes a lot of energy to break these bonds
Why do ionic compounds conduct electricity when aqueous or molten?
That ions separate and are free to move so they can carry the electric current
What is the rule for a compound named ‘something-IDE’ ?
Went to different elements combine the name is ‘something–IDE’
Eg: sodium + chlorine
= sodium chlorIDE
What is the rule for a compound named ‘something–ATE’ ?
When three or more different elements combine and one is oxygen the name is ‘something–ATE’
Eg: copper + sulphur + oxygen
= copper sulphATE
Are nitrates soluble or insoluble?
Soluble
Are common salts of sodium, potassium and ammonium soluble or insoluble?
Soluble
Are common chlorides soluble or insoluble?
Soluble
Which common chlorides are insoluble?
Silver chloride and lead chloride
Are common sulphates soluble or insoluble?
Soluble
Which common sulphates insoluble?
Lead, barium and calcium sulphate
Are common carbonates and hydroxides insoluble soluble?
Insoluble
Which carbonates and hydroxides are soluble?
Sodium, potassium and ammonium
How do you make an insoluble salt?
By reacting 2 soluble salts together
What is the method for making an insoluble salt?
- Mix the two solutions of the soluble salts together
- Filter out the precipitate of the insoluble salt
- Wash it with distilled water to get rid of impurities
- Dry it on filter paper
Why is barium sulphate used for x-rays?
It is opaque to x-rays.
It shows any problems like blockages in the body.
It is the known is a barium meal when drunken before an X-ray
Why is barium sulphate it safe to drink?
Because it is insoluble so it isn’t absorbed into the blood stream.
During a flame test what gives a yellow/orange flame?
Sodium ions (Na+)
During a flame test what is a lilac flame?
Potassium ions (k+)
During a flame test what gives a brick red flame?
Calcium ions (Ca2+)
During a flame test what gives a blue-green flame?
Copper ions (Cu2+)
What is the test for carbonates?
•bubbling a gas through limewater, if it turns milky colour it has CO2
What is the word equation for testing carbonates?
Acid + carbonate > salt + water + carbon dioxide
How do you test for sulphate ions?
- add dilute HCL with Barium chloride solution.
* If it white precipitate forms the original compound was a sulphate
What is the test for chloride ions?
- add dilute nitric acid with silver nitrate solution
* A chloride will give a white precipitate
What is spectroscopy ?
A way of identifying elements in a sample
The patterns of light emitted by the elements in a heated sample analysed
Why is spectroscopy good ?
- fast and reliable for even small amounts of elements in a sample
- helps discover new elements
