C2.2- Ionic Compounds and Analysis Flashcards
What is a cation?
Metal atoms loss electrons to form positively charged ions- cations.
What are anions?
Non-metals gain electrons to for, negatively charged ions called anions. The end of their names change to -ide.
How do ionic compounds form?
Positively charged ions are attracted to negatively charged ions, they form ionic bonds.
What groups form ionic compounds?
1,2,6,7
What charge do ionic compounds have?
They are neutral.
What is a compound ion?
An ion which contains more than one atom, for example NO3-. These are out in brackets when put in a formula with another ion.
What happens to the names of ions with oxygen present?
Their name ends with -ate.
How are ions in an ionic compound arranged?
They are arranged in a lattice structure. There are very strong bonds between positive and negative ions, which creates a strong electrostatic force between elements. These are ionic bonds.
What are the properties of ionic compounds?
They do not conduct electricity unless molten or in an aqueous solution because films can move freely.
They also have very high boiling and melting points because a lot of energy is required to break apart the strong electrostatic bonds.
What makes a substance soluble?
If it dissolves well in a particular liquid, the substance is soluble. If it doesn’t it is insoluble.
He are salts formed?
Salts are for,ed by reacting an acid with an alkali.
Which salts are soluble and which are insoluble?
All sodium, potassium and ammonium salts are soluble.
Sodium carbonate, potassium carbonate and ammonium carbonate; sodium hydroxide, potassium hydroxide, ammonium hydroxide- are all soluble.
Silver chloride, lead chloride are insoluble and most other chlorides are soluble. Lead sulphate , barium and calcium sulphate are insoluble, most other sulphates are. Melt carbonates and hydroxides aren’t soluble.
What are precipitates?
An insoluble coloured solid that forms when substance react together. They are insoluble salts formed when soluble reactants form an insoluble product
What are the state symbols?
G-Gas
L-Liquid
S-Solid
AQ- Aqueous.
Why are barium meals given to x-Ray patients?
It is given to patients to diagnose problems to do with the kidneys because x-Ray’s do not pass through barium sulphate, so images of the soft tissue can be developed. Most barium salts are toxic, however because barium sulphate is insoluble it doesn’t enter the blood and does not poison people.
