Vocab - states of matter term 1 Flashcards
1
Q
What is an atom?
A
The smallest neutral part of an element which can take part in chemical reaction.
2
Q
What is an element?
A
A substance made of one type of atom.
3
Q
What is a nucleus?
A
The central part of an atom.
4
Q
What is a proton?
A
Positively charged sub-atomic particle found in the nucleus.
5
Q
What is a neutron?
A
Neutral sub-atomic particle found in the nucleus.
6
Q
What is an electron?
A
Negatively charged sub-atomic particle found in the shells.
7
Q
What is relative mass?
A
The mass of something compared to the mass of something else.
8
Q
What is relative charge?
A
The charge of something compared to the charge of something else.
9
Q
What does the atomic number tell you?
A
The number of protons in an atom.
10
Q
What does the mass number tell you?
A
The number of protons and neutrons in the nucleus of an atom.
11
Q
What is relative atomic mass?
A
The mean mass of an atom relative to the mass of an atom of carbon-12, which is assigned the mass of 12.
12
Q
What is a period?
A
A horizontal row in the periodic table.
13
Q
What is a group?
A
A vertical column in the periodic table.
14
Q
What is an isotope? (NEED TO KNOW)
A
Different forms of the same element with the same number of protons but a different number of neutrons.
15
Q
What is relative abundance?
A
The amount of substance present compared to something else.
16
Q
What is the electron configuration?
A
The arrangement of electrons in shells around the nucleus.
17
Q
What is a particle model?
A
The theory of how particles behave in the three states of matter (solids, liquids, and gases).
18
Q
What is a physical change?
A
A change of state, which is reversible.
19
Q
What is a melting point?
A
The temperature at which a substance melts.
20
Q
What is sublimation? (NEED TO KNOW)
A
When a solid changes into a gas without becoming a liquid first.
21
Q
What is deposition?
A
When a gas changes into a solid without becoming a liquid first.
22
Q
What is a pure substance?
A
A substance made out of one type of particle.
23
Q
What is a mixture?
A
A substance made of different types of particles which are easily separated.
24
Q
What is filtration?
A
A separation method used to remove an insoluble solid from a liquid.
25
What does insoluble mean?
A substance that does not dissolve.
26
What does soluble mean?
A substance that does dissolve.
27
What is a solute?
The scientific name for the solid that dissolves.
28
What is a solution?
The mixture of the solute and solvent.
29
What is a solvent?
The liquid that dissolves the solute.
30
What is a saturated solution?
A solution that will not dissolve any more solute particles into it.
31
What is a filtrate?
The solution left after filtration.
32
What is residue?
The solid left in the filter paper after filtration.
33
What is chromotography?
A method used to separate coloured substances.
34
What is a mobile phase?
The solvent that absorbs up the paper in chromatography.
35
What is a stationary phase?
The paper or plate used in chromotography.
36
What is a chromotogram?
The result after chromotography is used to separate coloured substances.
37
What is a Rf value?
Retention factor: A measure of solubility calculated by dividing the distance the spot moves by the distance the solvent moves.
38
What is distillation?
The process that separates a mixture of two soluble substances using their boiling points.
39
What is fractional distillation?
A more detailed version of distillation that is used to separate lots of soluble substances e.g. crude oil.
40
What is desalination?
The removal of salt from sea water using evaporation.
41
What is aquifer?
Underground rocks containing groundwater.
42
What is sedimentation?
Small particles are allowed to settle out.
43
What is chlorination?
Adding chlorine to water to kill bacteria.
44
What is an ion?
A charged atom which has lost or gained electrons.
* If lost electron -> positive charge - metals
* if gained electrons -> negative charge - non metals.
45
What is an ionic bond?
A strong electrostatic force of attraction between oppositely charged ions.
46
What is an anion?
A negatively charged ion.
47
What is a cation?
A positively charged ion.
48
What are electrostatic forces?
The force of attraction between oppositely charged ions, repulsion between ions of the same charge.
49
What is an ionic lattice?
An arrangement of many particles bonded together in a fixed, regular pattern.
50
What is a poly atomic ion?
Ion made of two or more atoms bonded together. E.g. co3^2-
51
What is an anode?
A positively charged electrode.
52
What is a cathode?
A negatively charged electrode.
53
What is an aqueous solution?
Solution made from a solute dissolved in water.
54
What is a covalent bond?
A shared pair of electrons - 3 different types: simple, polymer and giant. (Non-metals ONLY)
55
What is a molecule?
Two or more atoms covalently bonded together.
56
What is valency?
The number of covalent bonds formed by an atom, or the charge on an ion.
57
What is an element?
A substance made of one type of atom.
58
What is a compound?
Two or more different elements chemically combined.
59
What is an intermolecular force?
A weak force of attraction between molecules.
60
What is a monomer?
A small molecule that can join with other molecules like itself to form a polymer.
61
What is a polymer?
A long chain molecule made form many smaller molecules (monomers) joined together.
62
What is a polyethene?
A common polymer made from ethane monomers.
63
What is an allotrope?
A different structure form of an element e.g. graphite and diamond are allotropes of carbon.
64
What is a giant covalent network/structure?
Many atoms joined together by covalent bonds E.g. diamond.
65
What are delocalised electrons?
Free moving electrons.
66
What is fullerene?
A molecule where each carbon atom is bonded to three other carbon atoms which produces spheres or tubes.
67
What is graphene?
An allotrope of carbon made of a sheet one atom thick, with a honeycomb shape.
68
What does malleable mean?
A substance that can be hammered or rolled into shape without shattering.
69
What is conductivity?
The ability to transfer energy.
70
What is metallic bonding?
Positively charged ions in a sea of delocalised electrons.
71
What does ductile mean?
Can be spread into wires.
72
What is an ionic compound?
A giant structure of ions.
73
What is it called when atoms share pairs of electrons?
They form covalent bonds. These bonds between atoms are strong.
74
What do covalently bonded substances consist of?
* may consist of small molecules
* some have very large molecules, such as polymers
* some have giant covalent structures (macromolecules) e.g. diamond, silicon dioxide.
75
How can a dot and cross diagram be used to show covalently bonded structures?
Shown as repeat units for polymers using a single like to represent a single bond, ball and stick and two- and three-dimensional diagrams.
76
Are small molecules or atoms smaller?
Atoms
77
What do simple molecular substances consist of?
Molecules in which the atoms are joined by strong covalent bonds.
78
Name the properties of ionic compounds.
* lonic compounds are made up of a metal and a nonmetal
* lonic compounds have regular structures (giant ionic lattices) in which there are strong electrostatic forces of attraction in all directions between oppositely charged ions.
* They have high melting and boiling points, because a lot of energy is required to break the many strong bonds.
* When melted or dissolved in water, ionic compounds conduct electricity because the ions are free to move and carry current, and they do not conduct electricity as solids, because the ions are fixed and are not able to move, carrying charge with them.
* Often dissolve in water to form an aqueous solution
79
Name the properties of simple molecular compounds.
* Substances that consist of small molecules are usually gases or liquids that have low boiling and melting points. They are made up of nonmetal elements.
*
Substances that consist of small molecules have weak intermolecular forces between the molecules. These are broken in boiling or melting, not the covalent bonds.
°
The intermolecular forces increase with the size of the molecules, so larger molecules have higher melting and boiling points.
* Substances that consist of small molecules don't conduct electricity, because small molecules do not have an overall electric charge. although, some breakdown in water to form ions which can conduct electricity
*
Many are insoluble in water, but some are soluble because they can form intermolecular forces with water which are stronger than those between water molecules or their own molecules already (e.g. CO, and NH, are soluble)
80
Name the properties of giant covalent structures.
*They are made up of nonmetal elements
* Substances that consist of giant covalent structures are solids with very high melting points.
* All of the atoms in these structures are linked to other atoms by strong covalent bonds.
* These bonds must be overcome to melt or boil these substances.
* some giant covalent structures can conduct electricity, whereas others can't
81
What are the properties of metals?
* Metals consist of giant structures of atoms arranged in a regular pattern. They are always made up of just metallic elements
* The electrons in the outer shell of metal atoms are delocalised and so are free to move through the whole structure.
* The sharing of delocalised electrons gives rise to strong metallic bonds.
* Metals have giant structures of atoms with strong metallic bonding.
* Therefore, most metals have high melting and boiling points.
* They can conduct heat and electricity because of the delocalised electrons in their structures.
* Conduction depends on the ability for electrons to move throughout the
metal.
* The layers of atoms in metals are able to slide over each other, so metals
can be bent and shaped.
* insoluble in water- but some will react with it instead
82
What are the properties of ionic compounds?
* high melting and boiling points - strong electrostatic forces
* conduct electricity when molten/dissolved - ions can move
* don’t conduct electricity when solid - ions are fixed in place.
83
What are the properties of typical covalent, simple molecular compounds?
* low melting and boiling points - only weak forces between molecules must be overcome, not covalent bonds.
* poor conduction of electricity - no charged particles of electrons that are free to move.
84
Diamond is an example of a giant covalent substance. Describe its structure.
* in diamond, each carbon is joined to 4 other carbons covalently
* it’s very hard, has a very high melting point and does not conduct electricity.
85
Graphite is an example of a giant covalent substance. Describe its structure.
* in graphite, each carbon is covalently bonded to 3 other carbons, forming layers of hexagonal rings, which have no covalent bonds between the layers.
* the layers can slide over each other due to no covalent bonds between the layers, but weak intermolecular forces. Meaning that graphite is soft and slippery.
* one electron from each carbon atom is delocalised
* this makes graphite similar to metals, because of its delocalised electrons.
* it can conduct electricity - unlike diamond.
86
What is diamond used for, and why?
Cutting tools - very hard, due to its rigid structure.
87
What is graphite used for, and why?
* electrodes - graphite can conduct electricity- unlike diamond
* lubricant - weak intermolecular forces and no covalent bonds between the layers, therefore it is soft and slippery.
88
What is graphene’ structure/bonding?
* single layer of graphite
* has properties that make it useful in electronics and composites
89
What is carbon’s structure/bonding?
* molecules of carbon atoms with hollow shapes
* they are based on hexagonal rings of carbon atoms, but they may also contain rings with five or seven carbon atoms
* the first fullerene to be discovered was Buckminsterfullerene (C60), which has a spherical shape.
90
What are carbon nanotubes’ structures/bonding?
* Cylindrical fullerenes with very high length to diameter ratios.
* Their properties make them useful for nanotechnology, electronics and materials.
91
How can fullerenes be used?
* They can be used as lubricants, to deliver drugs in the body and catalysts.
* Nanotubes can be used for reinforcing materials, for example, tennis rackets.
92
Describe the structure of polyethene.
* polymers have very large molecules
* atoms in the polymer molecules are linked to other atoms by strong covalent bonds.
* intermolecular forces between polymer molecules are relatively strong and so these substances are solids at room temperature.
93
What are the properties of metal?
* Malleable - the layers of atoms in metals are able to slide over each other
* can conduct electricity - delocalised electrons can move.
