Atomic Structure and Periodic Table

1) What is Matter ?
Anything that has mass and takes up space is recognised as matter. All stuff/materials are matter.

2) What is an Atom ?
This is the smallest unit of matter.
An atom can contain positive and negative charge
It is composed of three sub-atomic particles:
Proton - (found inside the nucleus) This is the positive charge (these cannot move)
Electron - (found outside the nucleus) This has the negative charge (these can move)
Neutron - (found inside the nucleus) This has a neutral charge

3) What is the approximate radius of an atom ?
1 x 10 (-10) m

4) What is a Nucleus ?
This is the central part of an atom containing just protons and neutrons.
The protons have a +1 charge
The outside part of an atom contains electrons that have a -1 charge.

5) What is the Atomic Number ?
The atomic number is the number of protons in the nucleus.
This is usually the top number in the periodic table.

6) What is the Mass Number ?
The mass number is the total number of protons and neutrons.
This is usually the bottom number in the periodic table.

7) What is an alpha particle ?
This is two neutrons and two protons.
Has low penetration.

8) What is a beta particle ?
This is one electron.
It has no mass and a charge of -1.
Has medium penetration.

9) What is a gamma ray ?
This is a not a particle (with mass)
It is pure energy released when an excited nucleus drops to a lower energy state.
Has very high penetration.

10) What is Ionisation ?
This is the removal (or addition) of an electrons (negative charge) from (or to) an atom.
There are two main types:
Positive ion - formed when an atom loses electrons
Negative ion - formed when an atom gains electrons

11) What is an Ion ?
An ion is an atom or molecule that carries an electric charge because it has gained or lost electrons.

12) What is Ionising Radiation ?
There are three types:
Alpha - when an alpha particle is emitted from the nucleus
Beta - when a beta particle is emitted from the nucleus
Gamma - when a gamma ray is emitted from the nucleus

13) What happens when a nucleus emits an alpha particle ?
The mass number (protons and neutrons) decreases by 4.
The atomic number (number of protons) decreases by 2.

14) What happens when a nucleus emits a beta particle ?
It undergoes beta decay.
This process involves a neutron transforming into a proton, an electron (the beta particle).
The electron is ejected from the nucleus at high speed, while the proton remains in the nucleus.
As a result, the atomic number of the nucleus increases by one, but the mass number (total number of protons and neutrons) remains the same.

15) What happens when a nucleus emits an gamma particle ?
The mass and charge remain unchanged.
No change in the atomic mass (protons + neutrons)
No change in the atomic number (number of protons)

16) What type of radiation is the most dangerous inside the body ?
Alpha radiation

17) What type of radiation is the same as a Helium Nucleus ?
Alpha radiation

18) There are several ways that an atom can be ionised ?
When an atom loses or gains an electron, this is called ionisation.
Radiation and Chemical Reaction

19) What is the Half-Life of a radioactive source ?
The time it takes for half of the radioactive nuclei in a sample to decay,

20) What is the Activity of a radioactive source ?
The rate at which the decay occurs, measured in Becquerels (Bq).
where 1 Bq = 1 decay per second.

21) What is an Isotope ?
Isotypes are different forms of the same element.
Same atomic number and same charge on the nucleus.
Different atomic mass number.
They have the same atomic number (number of protons) but they have a different mass number (number of neutrons).

22) What is a Mixture ?
Two or more different substances that have not been chemically bonded together.
In a mixture the different substances can be separated using a physical process.
A substance is not a mixture
eg - Sugar dissolved in water
eg - Iron and sulphur

23) Can you describe the following types of mixtures ?
Emulsion - Two liquids (one water based, one oil based)
Colloid - Different states of matter that are dispersed together
Foam - Gas bubbles trapped in a liquid
Gel - Liquid properties in a solid
Aerosol - Liquid or solid particles in a gas

24) How do you Create Mixtures ?
One way to create a mixture is to add a solid to a liquid and watch it Dissolve. For example salt in water.
The strong forces holding the particles together are broken down allowing the solid particles to mix with the liquid particles.
Solvent - The name given to the liquid substance that the solid is being dissolved into
Soluble - A solid substance is called soluble if it will dissolve
Insoluble - A solid substance is called insoluble if it will not dissolve
Solution - The name given to a mixture of a solid (solute) with a liquid (solvent) that does not separate out.

25) What is the difference between Compounds and Mixtures ?
Compounds - a substance made when two or more elements chemically bond together. Mixtures - a combination of substances physically mixed but not chemically bonded.
Compounds - requires a chemical reaction. Mixtures - no chemical reaction needed, just mixing.
Compounds - can only be separated by chemical methods (electrolysis, chemical reactions). Mixtures - can be separated by physical methods (filtration, distillation, evaporation, magnet).

26) How do you Separate Mixtures ?
If particles are not chemically bonded they can usually be separated.
There are a number of separation techniques (or physical methods) that can be used:
Filtration
This technique separates pieces of solid that are mixed with a liquid by pouring through filter paper.
Evaporation
This technique separates a soluble solid from a liquid (creating crystals)
Distillation
This technique separates a liquid from a solution (water can be separated from salty water) Uses evaporation and condensation to obtain a solvent from a solution
Chromatography
This technique separates different coloured liquids

27) What is an Element ?
Made of only one type of atom. Everything in the periodic table is an element.
O - one Oxygen atom
H2 - two Hydrogen atoms

28) What is a Molecule ?
Made of two or more atoms chemically bonded, due to a chemical reaction. They may or may not be the same type of atom.
H2 - two Hydrogen atoms
O2 - two Oxygen atoms
CO2 - different atoms

29) What is a Compound ?
Compounds are molecules that have different types of atoms
All compounds are molecules.
CO2

30) What is the difference between Molecules and Compounds ?
Molecules can be elements or compounds

31) What is the difference between Molecules and Elements ?
Elements are made up of only one type of atom.
Molecules can be made up of different types of atoms.

32) Give an example of a Molecule that is not a Compound ?
Molecules are elements when they are only made up of one type of atom
H2 - is not a compound

33) Give an example of a Compound that is also a Molecule ?
All compounds are molecules.
CO2

34) What is Crystallisation ?
This is a separation and purification process in which a solid forms from a solution, melt, or gas, creating an ordered, crystal structure.
It usually happens when a solution becomes saturated and then one of the following occurs: Cooling (the solubility decreases, so the solute comes out of solution) Evaporation (the solvent slowly disappears, leaving the solute behind) Changing the solvent (reduces solubility)
If you dissolve lots of salt in hot water and then let it cool, the salt begins to form crystals because the cooler water can't hold as much dissolved salt.

35) Can you describe how you would separate rock salt which is a mixture of salt and sand.
Grind the rock and mix it with water.
The salt will dissolve because it is soluble.
The sand will fall to the bottom it is insoluble.
The sand could be seperated by using filtration using filter paper
The salt could then be separated by using evaporation
The water could be seperated by using condensation by cooling down the water vapour.

36) Some changes are called Reversible ?
These materials will change when heated and then return to how they were before, when cooled down.
For example salt in water

37) Some changes are called Irreversible ?
Bicarbonate of soda will dissolve in vinegar

38) What is the Periodic Table ?
Every element has a name and a symbol (one or two letters)
Depending on the temperature every element can be changed into solid, liquid or gas.
The periodic table provides a list of all the different elements
The elements are arranged based on the atomic number (number of protons in the nucleus of each atom) and the physical and chemical properties of each element.
Each column is called a group and has similar physical and chemical properties.
The table is divided into groups (which go down) and periods (which go across)
For example the first group are all soft, shiny metals
All the elements in a column/group have similar properties
The properties of the elements change as you go down the column.
Elements at the bottom of the column/group act more violently than those at the top.

39) Do molecules get larger or smaller as you move down the group/column
larger ??

40) How many elements are there in the periodic table ?
118 in total. 95 metals (including 7 metalloids), 22 non-metals

41) Can you describe some physical properties of Metals ?
Metals conduct electricity
Metals conduct energy
Metals are strong and tough
Metals are shiny when polished
Metals are sonorous
Metals are ductile
Metals have high densities
Metals have high melting and boiling points

42) Can you describe some physical properties of Non-Metals ?
Non-metals don't conduct electricity
Non-metals don't conduct energy (by heating well)
Non-metals are not strong or hard wearing
Non-metals are dull
Non-metals are brittle
Non-metals have low densities
Non-metals have low melting and boiling points

43) What is a Metalloid ?
An element intermediate in properties between the typical metals and non-metals.

44) Can you list the 7 metalliods ?
Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium and Polonium

45) What are the Symbols for the following elements ?
Sulpur - S
Iron - Fe
Hydrogen - H
Carbon - C
Magnesium - Mg
Aluminium - Al
Sodium - Na
Chlorine - Cl
Calcium - Ca
Zinc - Zn
Oxygen - O
Copper - Cu
Potassium - K
Silver - Ag
Gold - Au

46) What groups are these elements in:
Sodium - Group 1
Magnesium - Group 2
Aluminium - Group 3
Carbon - Group 4
Nitrogen - Group 5
Oxygen - Group 6
Chlorine - Group 7
Helium - Group 0
Hydrogen - no group, at the top on its own

47) Can you describe where Group 0 is on the periodic table ?
It is the last column, on the far right.

48) What are the Halogens ?
These are non-metals with coloured vapours.
They are in group 7 of the periodic table.
Include: Bromine, Flourine, Chlorine, Iodine

49) What is Nuclear Fission ?
This is a nuclear reaction that can split a nucleus.
Unstable atoms include Uranium and Plutonium

50) What is Nuclear Fusion ?
This is a nuclear reaction that can combine nuclei together
This is the opposite of fission.

51) What is Mass and how can it be measured ?
Mass is a measure of the amount of matter in an object. Mass is usually measured in grams (g) or kilograms (kg).
It can be measured using a "top pan balance".

52) What is a Particle ?
Matter is made up of particles.
A particle can be an atoms (def above), molecules (def below) or ions (def above).
Particles are very small and cannot be seen with a microscope

53) Do particles get bigger when they are heated ?
No.

54) What is a Vacuum ?
A space with no particles of matter in it.

55) What is Brownian Motion ?
This is the name used to describe when particles move randomly in random directions and collide.

56) When does brownian motion occur ?
It occurs in liquids.
Solid particles suspended in a liquid.
Gas particles suspended in a air.
example - pollen grains in water

57) Why does brownian motion occur ?
This is caused by density fluctuations in the fluid.
The kinetic energy of the fluid molecules.

58) What will happen to the pressure of a gas held at constant volume if the temperature is decreased ?
The pressure will decrease.
Both pressure and temperature are directly proportional when volume is held constant.

59) What does Permeable mean ?
This is the name given to a material that allows liquids and gases to pass through it or soak into it.
eg Sandstone

60) What does Impermeable mean ?
This is the name given to a material that does not allow liquids or gases to pass through it.
eg Marble

61) What is Diffusion ?
This is the process where particles of one gas (or liquid) substance spread out in between the particles of another gas (or liquid) substance.
Diffusion in gases is much faster than diffusion in liquids
The particles spread out and move from an area of high concentration to an area of low concentration.
The following three factors affect the rate of diffusion: temperature, particle size and concentration

62) Do liquids diffuse faster than gases when at the same temperature ?
No.

63) What is Latent Heat ?
This is the extra heat needed to cause a substance to melt.
The stronger the intermolecular forces between the particles the more latent heat is needed to melt the substance.

64) What is Density ?
This is a measure of how many particles there are in a given space.
Gases are usually less dense than solids of the same substance.

65) What is the formula that connects density, mass and volume ?

Density = Mass / Volume 

66) When cooking oil is added to water, will it float or sink ?
The cooking oil has a density of 0.9 g/cm3.
Cooking oil will float because it has a lower density than water.

67) What is Conduction ?
Conductors are materials that allow heat to easily pass through it (metals)
The a conductor is heated the atoms increase their energy and vibrate more.
The atoms collide with other atoms, transferring energy and causing them to vibrate more.
The process of conduction continues until all the atoms have reached the same temperature.
Insulators are materials that are poor conductors (non-metals, gases, plastic)

68) What happens to the pressure and temperature increases ?
The hotter the particles the more kinetic energy they have.
This means particles move and seperate from each other more.
As temperature increases, pressure will increase and the density will decrease.

69) What is the difference between Physical Change and Chemical Change ?
Physical Change - its molecular composition stays the same. Affects only physical properties (shape, size, density). Can be easily reversed.
Chemical Change - its molecular composition is changed. Affects both physical and chemical properties. These are irreversible.

70) What is the Law of Conservation of Mass ?
This states that in any physical change or chemical reaction the total mass stays the same.
The number of particles at the start will equal the number of particles at the end

71) Do all Compounds have a Chemical Formula ?
Yes. The formula contains the symbols of the elements that make up the compound.
In a chemical reaction you start with "Reactants" and you end up with "Products".

72) What is a Chemical Reaction ?
This is a process in which one or more substances are converted into one or more different substances.

73) How do you Create a Compound ?
All compounds are formed from chemical reactions.
Some of these chemical reactions occur naturally, for example water (H2O) and carbon dioxide (CO2).
Water Synthesis is a chemical reaction in which two molecules of hydrogen combine with one molecule of oxygen.

74) How do you Separate a Compound ?
You need a chemical reaction to separate any atoms that have been chemically bonded.

75) What is a Substance ?
These include elements, compounds and mixtures.
It has the same properties all the way through.
Substances can be pure or impure.

76) What is a Pure Substance ?
A pure substance is made from just one type of element or one type of compound.

77) Is the air we breath a pure or impure substance ?
Impure because it contains different elements (nitrogen, oxygen) and compounds (cardon dioxide)
An impure substance contains more than one type of element or compound.

78) Is Salt a pure or impure substance ?
Pure because it only contains one type of compound (sodium chloride symbol - NaCl).

79) Can you describe these different types of substances ?
Base - a substance that reacts with an acid
Neutral - a substance that makes a solution with a PH=7
Salt - a substance made in a neutralisation reaction
Alkali - a substance that reacts with an acid that can dissolve in water to make a solution with a PH>7
Acid - a substance that contains hydrogen and can dissolve in water to make a solution with PH<7

80) What does Concentration mean ?
The measure of the number of solvent particles in a given volume of solution.

81) What is the difference between Density and Concentration ?
The Main difference is that concentration refers to how much of a substance is present in a mixture.
Whereas density refers to the mass of a substance per unit volume.

82) What does the word Dissolve mean ?
The process where a solute in a gaseous, liquid, or solid phase dissolves in a solvent to form a solution
example - adding ammonium nitrate to water
example - adding salt to water

83) What is a Catalyst ?
A chemical reaction will only take place if the particles have enough energy to react.
The particles need to have more than the 'activation energy' of the reaction.
A catalyst is a substance that reduces the activation energy.
This means the chemical reaction can take place will less energy that normal.
A catalyst is neither a reactant nor a product and is not used up in the reaction.

84) What is Water ?
It is the H2O compound in its liquid state.

85) Can gases dissolve in water ?
Yes

86) What is Ice ?
It is the H2O compound in its solid state.

87) When a compound changes from a solid to a liquid, the density normally decreases and the volume increases.
However H2O does the opposite.

88) When a compound changes from a liquid to a solid, does the density and volume increase or decrease ?
Density normally increases.
Volume normally decreases.
However H2O does the opposite.

89) Can you describe what happens when a solid dissolves ?
When something dissolves it does not disappear
There is no change in mass
If you evaporate off the liquid you will see the solid particles

90) What is the difference between Chloride and Chlorine ?
Chloride is formed from chlorine.
Chloride is what is created when Chlorine gains an electron and combines with other elements

91) What is a Carbonate ?
A carbonate is a salt of carbonic acid,
Carbonates are compounds containing CO32 ions.
Carbonates react with dilute acids to form a salt, carbon dioxide, and water.
example - calcium carbonate + hydrochloric acid = calcium chloride + carbon dioxide + water
example - copper2 carbonate = copper2 oxide + carbon dioxide

92) What is Decomposition ?
Also called chemical breakdown.
The process of simplifying a single chemical entity (normal molecule, reaction intermediate, etc.) into two or more fragments.

93) What is Smelting ?
This is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product.

94) What does "Extrusive Igneous" mean ?
Extrusive igneous rocks are formed by magma that has erupted onto the surface as lava and then cooled quickly.

95) What does "Intrusive Igneous" mean ?
Intrusive igneous rocks are igneous rocks formed inside of Earth's crust. They are formed as magma slowly cools and solidifies underneath Earth's surface.

96) What are CFCs ?
Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine.
They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants.

97) Can you describe some different types of polymers (or plastics)
nylon, polythene, PVC

98) What is Steel ?
Steel is an alloy of iron and carbon containing less than 2% carbon and 1% manganese and small amounts of silicon, phosphorus, sulphur and oxygen.
Steel is the world's most important engineering and construction material.

99) Why is Steel harder than pure Iron ?
Steel contains atoms of other elements as well as iron.
These atoms have different sizes to iron atoms, so they distort the layers of atoms in the pure iron.
This means that a greater force is required for the layers to slide over each other in steel.

100) Can you describe some different types of Ceramics ?
glass and porcelain

101) What is a Composite Material ?
These are materials that are made from two or more materials stuck together
The new material has different characteristics to the original materials.
eg - Fibre Glass (glass fibre and plastic)
eg - Concrete - sand, gravel and cement

102) What are Chemicals ?
This is the name given to substances that are used in a chemical reaction
Chemicals is another word for substances
The chemicals you start with are called the reactants
The chemicals you finish with are called the products
Chemical formulas are used to indicate what is happening in a chemical reaction
These chemical formulas are called symbol equations.

103) Can you describe what happens in a chemical reaction ?
atoms are not changed or destroyed
atoms move around
the mass does not change (the products weigh the same as the reactants)
there is always a transfer of energy to or from the surroundings

104) What are Nanoparticles ?

105) What is Titration ?

106) What is Graphene ?

107) What is the Silver Nitrate Experiment ?
These are the steps
Dissolve silver nitrate in distilled water
Place equal amounts of unknown metals in test tube
Submerge metals
Observe reactions after 30 secs
Record in table and list them from most vigorous to least

108) What is Photomining ?
This is a method of extracting metal compounds from low-grade ores using plants
When planted they absorb copper compounds through their roots and store it in their tissues
After grown, they are harvested and burned leaving ash
Ash contains copper compounds and then extracted from ash by electrolysis or displacement irons.

109) What is Bioleaching ?
Process using bacteria to break down low grade ores
Produce leachate containing metal compounds (can be extracted)

110) Why are pure metals soft ?
Layers can slide easily

111) Describe the structure of pure metals ?
Regular arrangement of identical atoms (shape + size) in layers

112) Metal + Water
Metal Hydroxide + Hydrogen
Calcium + Water = Calcium Hydroxide + Hydrogen

113) Metal + Acid
Salt + Hydrogen
Zinc + Hydrochloric Acid = Zinc Chloride + Hydrogen

114) Metal + Oxygen
Metal Oxide
Magnesium + Oxygen = Magnesium Oxide

115) What is the unit mol/dm(3) ?

116) Magnesium has 12 electrons, describe its electronic structure.

117) What is a Ceramic ?
Ceramics are made from heating non-metallic materials at high temperatures.
The properties of the ceramic material differ from the initial material.
The high temperature causes cyrstals to form on cooling and by controlling the speed of the cooling different size crystals can be made.
Rapid cooling creates small crystals and slow cooling creates large crystals.

118) What is Combustion ?
This is the reaction between a fuel and oxygen.
Carbon Dioxide is usually produced.
Energy moves from the chemical store to the thermal store.

119) What is Sublime ?

Atomic Structure Questions

120) What is the density of 14g of gold that has a volume of 10 cm3 ?
density = 14/10 = 1.4 g/cm3

121) What is the mass of 10cm3 of liquid that has a density of 1 g/cm3 ?
mass = density x volume
mass = 10 x 1 = 10g

122) What is the volume of 55g of pure water, if water has a density of 1 g/cm3
volume = mass / density
volume = 55 / 1 = 55 cm3

123) Balance the chemical equation
2Zn + O(2) = 2ZnO

Metal Displacement with Silver Nitrate is a redox reaction
where the more reactive metal reacts with the silver nitrate causing
the solid metal to lose electrons (oxidize) plus oxygen
and the silver ions gain electrons (reduce) minus oxygen