C1 Flashcards
What are atoms?
Atoms is the smallest known matter
What are elements?
Elements are pure substances made up of only one type of atom
What are compounds?
Compounds are two or more elements that are chemically combined
What are mixtures?
Mixtures are two or more elements that are NOT chemically combined
What method is used to separate an insoluble solid from a liquid?
Filtration
What method is used to separate a dissolved solid from a liquid( in other words an aqueous solution)?
Crystallisation
Can you explain crystallisation?
Name the apparatus first.
Evaporation basin
Solution
Bunsen burner
Tripod
- Place the evaporation basin (with the solution inside)on the tripod and heat is using the Bunsen burner.
- Heat it until most of the liquid is gone then turn the bunsen burner off and let what’s left cool
- Leave ur solid to dry in a cool place, put it in the oven or pat it with a paper towel
What is simple distillation?
The removal of a liquid solvent from a dissolved solid.
Can you explain simple distillation?
Name apparatus first.
Tripod
Thermometer
Condenser
Solution cold water
Conical flask
Round bottom flask
1. Heat the solution in the round bottom flask flask (using the tripod and Bunsen burner ) until it’s the boiling point of the liquid
2. Use the thermometer to make sure the boiling point is correct
3. The evaporating liquid with travel down a tube into the condenser
4. The gas will condensate in the condenser and turn into a liquid
5. The liquid is collected in a conical flask below the condenser
How does the condenser work
Cold water is run through it, the cold water will cool the condenser
What is fractional distillation used for
Fractional distillation is used to separate two liquids with different boiling points
Explain fractional distillation?
Apparatus l?
The set of is the exact same as distillation except for two things: the fractionation column and a heater(for flammable liquids)
Repeat the same process as done with distillation.
The fractionating column is useful just in case the boiling points of the two liquids are similar .
The fractionating column slows the evaporation of the liquids lowering the chances of the liquids mixing together as a gas.
A heater is used instead of a Bunsen burner just in case you are separating a flammable liquid
How do you check the purity of ethanol and water?
By measuring their boiling points.
What’s the boiling point of ethanol and water
Water should be 100 degrees and ethanol should be 78 degrees
Who created the plum pudding model and what does it represent
Thompson.
A ball of positive charge with negative electrons embedded in it
What was the gold foil scattering experiment , who was it conducted by?
Rutherford and his team
A beam of alpha particles was shot at gold foil
What was the results of the gold foil experiment and what did it suggest
The Majority of the alpha particles went straight through the foil. However some deflected in different directions.
This suggested that most of an atom was empty spaces and all the mass was positive charge contained in a tiny centre of the atom called the nucleus
Who discovered energy shells?
Bohr. He suggested that electrons orbited the nucleus at different fixed distances
Who discovered neutrons
Chadwick. He found more particles in the nucleus. They didn’t have a charge but they did have mass, they are called neutrons
What is the charge and mass of Protons , Neutrons and Electrons ?
Protons:
Mass= +1
Charge= +1
Electrons:
mass= + 0
Charge = -1
Neutrons:
Mass= +1
Charge =0
What’s the atomic number
Total mass of protons in an atom
What’s the mass number
Total number of neutrons and protons in the nucleus
What’s the correlation between the amount of protons and electrons
An atoms always has the same amount of electrons as neutrons
What are isoptopes
Same elements different number of neutrons
How to calculate relative atomic mass
(% abundance x mass of isotope) + (% abundance x mass of isotope)
——————————————————
100
Who is Mendeleev and why is he called the grandfather of the periodic table
Founder of periodic table
Mendeleev discovered that there are more elements to be discovered and predicted their possible properties, so he left spaces in the periodic table where he thought elements were undiscovered.
The periodic table was filled out with elements of the same properties he predicted.
What is the law of octaves and who created it?
Newlands.
Every 8 elements their properties repeated
What is the periodic table ordered in
Atomic number
What is the rule of groups of the periodic table
The group number is the a same as the amount of electrons in the outer shell
What is the rules of the periods of the periodic table
The further down the period the more electron shells there are.
EG: 5th period = 5 electronic shells
Properties of metals
Solid
Hard
Shiny
Malleable
Makes up majority of the table
Properties of non metals
Gasses or liquids
Solids with low melting point
Right top of periodic table
What are the elements in Group 7 of the periodic table commonly known as?
Halogens
True or False: Halogens are all gases at room temperature.
False
Fill in the blank: The most reactive halogen is _______.
Fluorine
Which halogen is commonly used as a disinfectant in swimming pools?
Chlorine
What is the trend in reactivity as you move down the group of halogens?
Reactivity decreases
Why does the reactivity of halogens decrease down the group
Group 7 elements attract electrons. The further away the electrons on the outer shell are from the protons in the nucleus, the harder it is for the nucleus to attract an electron
Properties of halogens
Reactive
low melting point
Low boiling point
Are in Pairs( diatomic)
What is a diatomic atom
An atom that is too unstable to stay single so it Pairs with another of the same atom .
Eg: Cl2
When metals and a halogen reacts together what is the product called
Metal halide
What are the group 0 elements called
Noble gasses
Properties of noble gases
Very stable- full outer shell
Unreactive
Low boiling point
Does not form molecules
Increasing density down the group
