3.1 - Introduction Flashcards
What make good observations?
- Solid, liquid or gas?
- Coloured or colourless?
- Crystalline or powdered? (for solids)
- Clear or cloudy? (for liquids)
Things that make a physical change physical.
- Create no new substances.
- Are usually easy to reverse
- Absorb or release small amounts of energy.
What things that make a chemical change chemical.
- Create new substances.
- Are usually difficult to reverse.
- Absorb or release large amounts of energy
Tests For Water
One chemical test for water is?
Anhydrous copper(II) sulphate: turns from white to blue
One example of a physical tests for water is?
Melting point (MP) = 0 oC
Another example of a physical tests for water is?
Boiling point (BP) = 100 oC
What is a solute?
The substance which is going to be dissolved
What is a solvent?
The liquid which is going to do the dissolving
What is a solution?
The resulting mixture of solute dissolved in solvent
What is a saturated solution?
A solution in which no more solute can be dissolved
What is a suspension?
A solid floating in a liquid because it cannot dissolve
What does soluble mean?
A substance which can be dissolved
What does insoluble mean?
A substance which can’t be dissolved
We measure solubility per how many grams?
We measure solubility in g per 100 g of solvent
Solubility varies with what?
Solubility varies with temperature.
On a solubility graph the line shows what?
Shows the maximum mass of solid which can be dissolved at each temperature.
On a solubility graph the part above the line shows what?
More than the maximum mass of solid, so some will dissolve and some won’t.
On a solubility graph the bit below the line shows what?
Less than the maximum mass of solid, so it will all dissolve.
what is the definition of an element?
An element is a substance containing only one type of atom.
What are the properties of non-metals?
Non - Metal Properties: Low MP/BP Electrical insulators Brittle Dull
What are the properties of metals?
Metal Properties: High MP/BP Electrical conductors Malleable Shiny
Where can you find the symbols for elements?
For most elements, their chemical formula is also their symbol from the periodic table.
Which elements are diatomic?
Hydrogen - H2 Nitrogen - N2 Oxygen - O2 Fluorine - F2 Chlorine - Cl2 Bromine - Br2 Iodine - I2 Astatine - At2
What shape do diatomic elements take.
Number 7 plus hydrogen.
What is the definition of a compound?
A compound is a substance containing more than one type of atom, chemical bonded together.
How can compounds be formed?
Compounds can often be formed by heating their elements together.
True or false:
The properties of a compound are identical to the properties of the elements it was made from.
False:
The properties of a compound are usually totally different from the properties of the elements
the compound is made from.
Finish the sentence:
There are three types of compound, each containing a different type of chemical ___________.
Bonding
