Flashcards in Unit 1-Atomic structure and periodic table. Deck (86):
What do atoms contain?
The nucleus of an atom...
-Is in the middle of the atom.
-Contains protons and neutrons.
-Has apositive charge.
-Almost whole mass is concentrated in the nucleus.
What is a protons relative mass and charge?
1 and +1
What is a neutrons relative mass and charge?
1 and 0
What is an electrons relative mass and charge?
0 and -1
The electrons in an atom...
-Move around the nucleus in electron shells.
-They are negativity charged.
-Virtually no mass.
What is an atoms overall charge? why?
Neutral because they have the same number of protons as electrons.
What is an ion?
An atom or a group of atoms that has lost or gained electrons.
What does the atomic number tell you?
How many protons there are.
What does the mass number tell you?
The total number of protons and neutrons there are in an atom.
How do we find out the number of neutrons?
Subtract the atomic number from the mass number.
It is the number of ? in the nucleus that decides what type of atom it is.
What is the carbon symbol?
What is the magnesium symbol?
What is the nitrogen symbol?
What is the magenese symbol?
What is the lead symbol?
What is the oxygen symbol?
What is the iron symbol?
What is the sodium symbol?
What is an isotope?
Different forms of the same element which have the same number of protons but a different number of neutrons.
Relative atomic mass =?
(isotope abundance x isotope mass number) divided by abundance of all the isotopes
When elements react, atoms combine together to form ...
What are compounds?
Substances formed from two or more elements, the atoms of each are in fixed proportions throughout the compound and they are held together by chemical bonds.
A compound which is formed from a metal and a non metal consists of ...
When a non metal and a metal react the metal atoms...
Lose electrons to form positive ions.
When a non metal and a metal react the non metal atoms...
Gain electrons to form negative ions.
Give some examples of ionic bonding ...
A compound formed from non metals consists of ...
Give some examples of covalent bonding...
What is sodium chlorides formula?
What is hydrochloric acids formula?
What is carbon monoxides formula?
How many atoms are in one particle of Na2CO3
The molecules on the left hand side of the equation are called the...
The molecules on the right hand side of the equation are called the....
True or false.... in a mixture there are no chemical bonds
What is air a mixture of?
Nitrogen,oxygen,carbon dioxide,argon and others
How to do paper chromatography (6marks)
1)draw a line near the bottom of the filter paper in pencil
2)add a spot of ink to the line and place the sheet in a beaker of solvent
3)make sure the ink isn’t touching the water
4)the solvent seeps up the paper carrying the ink with it
5)if any of the dyes are insoluble then they will stay at the baseline
6)the result is a chromatogram
The point the solvent has reached in chromatography as it moves up the paper is the ...
Why does the line at first need to be in pencil?
It is insoluble.
What is filtration used for?
-If your product is an insoluble solid that needs to be separated from a liquid reaction mixture.
Which two separation techniques can be used to separate soluble solids from solutions?
Evaporation and crystallisation.
If a solid is dissolved it is ...
What is simple distillation?
A method used to separate a liquid from a solution.
What is the disadvantage to simple distillation ?
You can only use it to separate things with very different boiling points.
How do you do simple distillation (4 marks)
-The solution is heated and the part of the solution that has the lowest boiling point evaporates first
-The vapour is then cooled and condenses
-The rest of the solution is left in the flask
What is fractional distillation?
A method used to separate a mixture of liquids.
How do you do fractional distillation?(6 marks)
-You put the mixture in a flask and stick a fractionating column on top then heat it
-The different liquids will all have different boiling points and so will evaporate at different temperatures
-The liquid with the lowest boiling point evaporates first.when the temperature on the thermometer matches the boiling point of this liquid ,it will reach the top of the column
-Liquids with a higher boiling point may also start to evaporate but the column is cooler towards the top so they will only get part the way up before condensing and running back into the flask
What did John Dalton think about atoms?
They were solid spheres and that different spheres made up different elements.
What did Thomson create?
The plum pudding model.
What did Thompson find?
That the atom must contain even smaller negatively charged particles called electrons.
How did Rutherford prove the plum pudding model was wrong?
By firing negatively charged alpha particles at an extremely thin sheet of gold.
What was rutherfords results?
Some negative alpha particles passed through however some were deflected slightly which means it must have a positive nucleus.
What was rutherfords model called?
The nuclear model.
What did Bohr do?
Changed the nuclear model of the atom a bit.
What did Bohr find?
That electrons orbit the nucleus in fixed shells.
How many electrons can the first shell have?
How many electrons can the second shell have?
Which group has full electron shells?
What is hydrogen’s proton number?
What is helium’s proton number?
If nitrogen has an atomic number of 7 what is its electronic configuration?
If magnesium has an atomic number of 12 what is it’s electronic configuration?
What was a problem with the way the elements were recorded in the periodic table in the early 1800s?
It didn't take their properties in to account.
Why were gaps left in Dmitri Mendeleev's version of the periodic table?
For undiscovered elements and so he could predict their properties.
When metals react what type of ions do they form?
What are some physical properties of metals?
-High boiling points and melting points.
What are some properties of transition metals?
What are the alkali metals?
What are the trends as you go down group 1?
-Lower melting and boiling points.
-Higher relative atomic mass.
What do group 1 elements react to form?
Ionic compounds that are usually white solids that dissolve to form a colourless solution.
What happens when group 1 elements react with water?
They react vigorously to produce a hydrogen gas and metal hydroxides.The lower down the metal is the more vigorous the reaction is.
What is fluorine?
A very reactive,poisonous, yellow gas.
What is chlorine?
A fairly reactive, poisonous, dense green gas.
What is bromine?
A dense, poisonous, red-brown, volatile liquid.
What is iodine?
Iodine is a dark grey crystalline solid or a purple vapour.
As you go down group 7...
-The elements become less reactive.
-The elements have a higher melting and boiling point.
-The elements have higher relative atomic mass.
Halogen atoms can share electrons with other metals via what type of bonding?
What do halogens form when they react metals?
1- ions called halides.
What are group 0 elements called?
How many electrons do group 0 elements have in their outer shell?
8 apart from helium which has 2
All elements in group 0 are...
Monatomic gases, colourless and non-flammable.
What happens to the boiling point as you move down group 0?
Why does the boiling point increase as you go down group 0?
It’s due to the increase in the number of electrons in each atom leading to greater intermolecular forces which are harder to overcome.