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96 Cards in this Set
- Front
- Back
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What is an atom? |
A tiny particle which can be part of a substance or material |
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What is an element? |
A substance made up of one type of atom |
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What are the vertical lines in the periodic table called? |
Groups |
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What are the horisontal lines in the periodic table called? |
Periods |
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What does the black line on the periodic table divide? |
Metals and non metals |
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What are metalloids? |
Elements which have both metal and non metal properties |
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Give examples of metalloids |
Silicon and geranium |
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What are compounds? |
Different types of atoms bonded together |
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What do atoms include |
A nucleus, with protons and neutrons Outer shells with electrons |
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What different parts are there to an equation? |
The reactants and products |
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What are the reactants in a chemical equation? |
The substances you start with |
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What are the products in a chemical equation? |
The new substances made |
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What happens to atoms in chemical reactions? |
They get rearranged |
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What are symbol equations? |
Equations which use chemical symbols |
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What is a balanced equation? |
An equation where there is the same number of each type of atom on both sides of it |
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What is the law of conservation of mass? |
'The total mass of the products formed in a reaction is equal to the total mass of the reactants' |
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When can the law of conservation of mass be broken? |
If the reaction involves gases and is carried out in open containers such as test tubes or conical flasks |
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How can you check if an equation is balanced? |
You can check if an equation is balanced by counting the number of each type of atom on either side of the equation. If the numbers are equal, then the equation is balanced |
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What are state symbols? |
State symbols identify the type of substance in a chemical equation |
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What is the state symbol for solid? |
s |
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What is the state symbol for liquid? |
l |
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What is the state symbol for gases? |
g |
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What is the state symbol for substances dissolved in water (aqueous solutions) |
aq |
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What is a mixture? |
A mixture is made up of two or more substances (elements or compounds) that are not chemically combined together |
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What are the differences between compounds and mixtures |
Compounds have a fixed composition, mixtures have no fixed composition Chemical reactions must be used to separate the elements in a compound, in mixtures the different elements or compounds in a mixture can be separated again more easily There are chemical bonds between atoms of the different elements in the compound but there are no chemical bonds between atoms of the different substances in a mixture |
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What physical means can you use to separate a mixture? |
Filtration Crystallisation Distillation Chromatography |
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What do you use filtration for? |
To separate substances that are insoluble in a particular solvent from those that are soluble in the solvent. |
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What do you use Crystallisation for? |
Crystallisation is often used to separate salt from water. To obtain a pure form of salt from the salt solution you can evaporate the water from it. Heating should be stopped when the solution is at the point of crystallisation. |
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What do you use distillation for? |
You can use distillation when you want to get both a solute and a solvent without losing one in crystallisation. |
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How can you perform simple distillation? |
In simple distillation, a solution is heated and boiled to evaporate the solvent. The vapour given off then enters a condenser. This is an outer glass tube with water flowing through it that acts like a cooling jacket around the inner glass tube from the flask. Here the hot vapour is cooled and condensed back into a liquid for collection in a receiving vessel. |
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What can distillation also be used for? |
Separating mixtures of miscible liquids such as ethanol and water. |
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What does the word miscible describe? |
The word miscible describes liquids that dissolve into each other, mixing completely. |
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How can you perform fractional distillation ? |
By adding a fractioning column to the apparatus for distillation. This is usually a tall glass column filled with glass beads. |
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What is the boiling point of ethanol? |
78oC |
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What is the boiling point of water? |
100oC |
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How is fractional distillation used in the alcoholic spirits industry? |
Fractional distillation is used to separate ethanol from a fermented mixture in the alcoholic spirits industry and in the use of ethanol as a biofuel |
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How can you perform paper chromatography? |
By dabbing a spot of the solution on a pencil line near the bottom of a sheet of absorbent chromatography paper. The paper is then placed standing in a solvent at the bottom of a beaker or tank. The solvent is allowed to soak up the paper, running through the spot of mixture. The more soluble a substance is in the solvent, the further up the paper it is carried. |
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When did strong experimental evidence first show the existence of particles and atoms? |
the early 1800s |
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Who first discovered evidence about the existence of atoms and particles? |
John Dalton |
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Who first discovered the electron? |
J.J. Thomson |
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When was the electron discovered? |
At the end of the 1800s |
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When was the evidence of neutrons confirmed? |
1932 |
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Who first confirmed the evidence of neutrons? |
James Chadwick |
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What are the two types of sub atomic particles in the nucleus? |
Protons and neutrons |
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What charge do protons have? |
Positive |
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What charge do neutrons have? |
Negative |
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What charge do electrons have? |
Negative |
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What is the overall charge on an atom? |
There is none. Because every atom contains equal numbers of protons and electrons, the positive and negative charges cancel out. |
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What is the atomic number? |
The number of protons in each atom (and electrons) |
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What is the mass number? |
The number of protons plus neutrons in the nucleus in an atom |
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What is an ion? |
An ion is a charged atom (or group of atoms) |
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If an atom has more electrons than protons, it is a.. |
negative ion |
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If an atom has more protons than neutrons, it becomes a... |
positive ion |
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What are isotopes? |
Atoms of the same element with different numbers of neutrons |
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What is electronic structure? |
The way you can draw an atom and its electrons |
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What do the chemical properties of an element depend on? |
How many electrons ithas. |
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What did John Dalton first arrange the elements into? |
A table in order of their atomic weights (The Table of Elements) |
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Who improved John Dalton's table of elements? |
John Newlands |
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Who invented the Periodic Table? |
Dmtri Mendeleev |
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Which element does not correctly fit into the periodic table? |
Argon |
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What are chemical elements placed in the order of in the periodic table? |
Their atomic number |
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How many groups are in the periodic table? |
8 |
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What does the group number in the periodic table tell you about the elements? |
The number of electrons in the outermost shell |
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Do metals or non-metals conduct electricity? |
Metals |
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What does it mean if a material is ductile? |
It can be drawn out into wires |
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What does it mean if a material is malleable |
It can be hammered into shapes without smashing |
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How many electrons do Group 0 atoms have in the outer shell? |
8/full shell |
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What does monatomic mean? |
single-atom |
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What is the general trend in boiling points in Group 0? |
The boiling points of noble gases get higher going down Group 0 |
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What are the Group 1 metals called? |
The alkali metals |
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What are the alkali metals? |
lithium, sodium, potassium, rubidium, caesium and francium |
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What do the alkali metals have to be stored in because of their reactivity? |
Oil |
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What is the trend in reactivity as you go down Group 1? |
The reactivity increases as you go down the group. |
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What is the trend in density with the alkali metals? |
All alkali metals have a very low density compared with other metals
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Are the alkali metals soft or hard? |
Soft |
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Why are the alkali metals so reactive? |
Because they only have 1 electron in their outermost shell |
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What is the trend in boiling points in Group 1? |
Going down the group,the melting points and boiling points get lower and lower |
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How do Group 1 metals react in water? |
They move around fizzing because the metal reacts to form hydrogen gas |
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What are the Group 7 elements called? |
The halogens |
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Are the halogens metals or nonmetals? |
non-metals |
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What is the general trend of melting and boiling points in Group 7? |
They have low melting points and boiling points which increase going down the group |
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Are the halogens good or poor conductors of electricity? |
Poor conductors |
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What are diatomic molecules? |
Molecules with two atoms |
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How many electrons do halogens have in their outermost shell? |
7 |
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What is the general trend of reactivity in Group 7? |
The elements get less reactive as you go down the group |
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What is the rule in test tube reactions with halogens? |
A more reactive halogen will displace a less reactive halogen from solutions of its salts |
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What is the rule with Group 1 elements and reactivity? |
The elements get more reactive as you go down the group |
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What is the rule with Group 7 elements and reactivity? |
The elements get less reactive as you go down the group |
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Why does reactivity increase going down Group 1? |
Reactivity increases going down Group 1 because the atoms get larger so the single electron in the outermost shell (highest energy level) is attracted less strongly to the positive nucleus. |
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Why does the reactivity decrease going down Group 7? |
Going down the group, the outermost shell's electrons get further away from the attractive force of the nucleus so it is harder to attract and gain an extra incoming electron. |
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What are transition elements? |
The transition elements, which are all metals are positioned in the large central block of the periodic table between Group 2 and Group 3. This block contains the transition elements, also called the transition metals. |
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What properties do the transition elements have? |
- They are good conductors of electricity and thermal energy - They are hard and strong - They have high densities - They have high melting points (with the exception of mercury, which is a liquid at room temparature) |
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List the formed coloured compounds from the transition elements |
- Copper sulfate, which is blue - Nickel carbonate which is pale green - Chromium oxide which is dark green - Manganese chloride which is pale pink |
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Why do some compounds include a roman number? |
Because transition elements can form more than one ion. For example, iron may exist as Fe2+ or Fe3+ . Compounds of these ions are different colours. |
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What is a catalyst? |
A catalyst is a substance that speeds up a chemical reaction, but is not consumed by the reaction; hence a catalyst can be recovered chemically unchanged at the end of the reaction it has been used to speed up, or catalyze. |
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What transition elements are used as catalysts for example? |
Nickel and iron |
