Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

chem > chemistry module 3 definitions > Flashcards

chemistry module 3 definitions Flashcards

(62 cards)

Start Studying
1
Q

bohr model

A

small dense positive nucleus with electrons orbiting around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

first ionisation energy

A

the removal of one mole of electrons from one mole of gaseous
atoms. Factors which affect the first ionisation energy are: the strength of attraction between
the electron and the nucleus, the nuclear charge and the atomic radius. There is a small
decrease in first ionisation energy due to s- and p-subshell energies (between Be and B) and
p-orbital repulsion (between N and O)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

giant covalent lattice

A

a network of atoms bonded by strong covalent bonds (e.g. carbon
(diamond, graphite and graphene) and silicon). Giant covalent lattices typically insoluble with
a high melting and boiling point due to the presence of strong covalent bonds. They are also
poor electrical conductors as they don’t contain mobile charged particles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

giant metallic lattice structure

A

the structure of all metals, made up of cations and
delocalised electrons. Giant metallic structures are typically insoluble with a high melting and
boiling points due to strong electrostatic forces of attraction between cations and electrons.
Metals are good electrical conductors due to the presence of delocalised electrons (mobile
charges).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

group

A

column

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

period

A

row

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

metallic bonding

A

strong electrostatic attraction between cations and delocalised electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

p block

A

the part of the periodic table which have their highest energy electron in a p orbital (same for s, f and d orbital if u just switch stuff out)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

periodicity

A

a repeating trend in physical and chemical properties across the periods of the
periodic table

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

successive ionisation energies

A

the energy required to remove each electron one-by-one
from one mole of gaseous atoms / ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

base

A

a substance that can accept H+
ions from another substance. Group 2 compounds can
be used as bases: Ca(OH)2
is used to neutralise acidic soils in agriculture and Mg(OH)2
and
CaCO3
are used as antacids to treat indigestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

electron configuration

A

the arrangement of electrons into orbitals and energy levels around
the nucleus of an atom/ ion. Group 2 elements have an s2
outer shell electron configuration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

group 2 oxides

A

a compound with the general formula MO, where M is a group 2 element.
When group 2 oxides react with water, they form an alkaline solution, with alkalinity
increasing down the group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

oxidation

A

-loss of electrons
-increase in oxidation number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

reduction

A

-gain of electrons
-decrease in oxidation number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

second ionisation energy

A

the removal of one mole of electrons from one mole of gaseous
1+ ions to form one mole of 2+ ions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

boiling point

A

the temperature at which a liquid boils and becomes a gas. Boiling point
increases down group 7 due to the increasing strength of London Forces between the
halogen molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

diatomic molecules

A

molecules made up of 2 atoms. halogens and oxygen are diatomic. if there aren’t 2 then there will be a free radical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

displacement reaction

A

a reaction in which one atom is replaced by another. Halogens can
undergo displacement reactions as their reactivity decreases down the group. The more
reactive halogen will displace the less reactive halogen from a solution of its salt.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

disproportionation reaction

A

wherein the same element is both oxidised and reduced and this happens in chlorination where chlorine is added to water to purify it and reaction between chlorine and cold, dilute aqueous sodium hydroxide to form bleach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

electron configuration

A

the arrangement of electrons into orbitals and energy levels around
the nucleus of an atom / ion. The halogens have a s2p
5
outer shell electron configuration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

precipitation reaction

A

a reaction in which two aqueous solutions are combined to form an
insoluble salt (a precipitate). Halide anions undergo precipitation reactions with aqueous
silver ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

water treatment

A

the addition of chlorine to water to kill bacteria. The risks associated with
the use of chlorine to treat water are the hazards of toxic chlorine gas and the possible risks
from the formation of chlorinated hydrocarbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

anion

A

negatively charged ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
cation
positively charged ions
26
ammonium ion
an ion with the formula NH4+ . The test for ammonium ions is a reaction with warm NaOH, which forms NH3
27
carbonate
a salt containing the CO3 2- anion. A reaction between a carbonate and H+ will form CO2 (g)
28
halide
a salt containing a group 7 anion. Cl- , Br- and I- can be tested for using a solution of silver ions as this reaction forms a coloured precipitate. The solubility of the precipitate is then tested using dilute and concentrated ammonia.
29
sulfate
a salt containing the anion SO4 2-. A reaction between SO4 2- and Ba2+(aq) will form a precipitate
30
order of experiments to test for anions
1) carbonates 2) sulphates 3) halides
31
carbonates
add an acid which would mean it forms co2 so bubble the gas through limewater and it should turn cloudy
32
sulphates
- add dilute hcl - add dilute barium chloride or barium nitrate -if a white precipitate of barium sulphate forms then sulphates present
33
halides
add silver nitrate ions cl= white br= cream iodide= yellow
34
hallide test alt
add dilute ammonia - if dissolves then its a chloride add conc ammonia - if dissolves then its a bromide if nothing then iodide
35
test for ammonium ions
Add a few drops of dilute sodium hydroxide solution, then warm gently. Ammonia gas is produced if ammonium ions are present. damp red litmus paper should turn blue if they are present as ammonia is an alkali
36
activation energy
the minimum energy required for a reaction to take place
36
average bond enthalpy
the energy required to break one mole of gaseous bonds. Actual bond enthalpies may differ from the average as the average bond enthalpy considers a particular bond in a range of molecules
37
endothermic
a reaction which takes in energy (ΔH is positive). More energy is required to break bonds than is released by making bonds. energy of reactants > products
38
exothermic
a reaction which gives out energy (ΔH is negative).More energy is released by making bonds that are needed to make them. energy of reactants< energy of products
39
enthalpy (H)
a value that represents the heat content of a system
40
enthalpy change (ΔH)
the change in the heat content of a system during a reaction. This can be determined from experimental results using q = mcΔT (where q is the heat change of the surroundings, m is the mass of the surroundings, c is the specific heat capacity and ΔT is the change in temperature).
41
enthalpy change of combustion
the enthalpy change that takes place when one mole of a substance is completely combusted.
42
enthalpy change of formation
the enthalpy change that takes place when one mole of a compound is formed from its elements
43
enthalpy change of neutralisation
the enthalpy change that takes place when one mole of water is formed from a neutralisation reaction.
44
enthalpy change of a reaction
the enthalpy change that is associated with a particular chemical equation.
45
enthalpy profile diagram
shows the difference in the enthalpy of reactants and products as well as the activation energy of a reaction
46
hess' law
the enthalpy change of a reaction is independent of the route it takes
47
standard conditions
a pressure of 100 kPa and a temperature of 298K.
48
standard states
the physical state (s, l, g, aq) of a substance under standard conditions.
49
boltzmann distribution graoh
a graph showing the distribution of the energies of molecules in relation to the activation energy. Increasing temperature will increase the proportion of molecules with energy above the activation energy. A catalyst lowers the activation energy meaning more molecules will have sufficient energy to react.
50
catalyst
: a substance that speeds up the rate of a reaction without being used up. A catalyst allows the reaction to proceed via a different route with a lower activation energy. Catalysts are important in terms of economics and sustainability as they enable processes to take place at lower temperatures meaning less energy is required (this decreases the combustion of fossil fuels so CO2 emissions are reduced).
51
collision theory
the theory which states that molecules must collide with sufficient energy at the correct orientation for a reaction to occur
52
concentration
: the amount of a substance that is dissolved per unit volume of solution. Increasing the concentration increases the rate of reaction as there are more molecules in the same volume meaning more frequent successful collisions.
53
enthalpy profile diagram
shows the difference in the enthalpy of reactants and products as well as the activation energy of a reaction.
54
heterogeneous catalyst
a catalyst that is in a different state to the reactants (e.g. a solid catalyst with gaseous reactants)
55
homogeneous catalyst
a catalyst which is in the same state as the reactants.
56
pressure
the force that a gas exerts on the walls of a container. Increasing the pressure increases the rate of reaction as there are more molecules in the same volume (or the same number of molecules in a smaller volume) meaning more frequent successful collisions.
57
rate of reaction
a measure of how quickly a reactant is used up/ a product is formed. Rate can be determined by measuring concentration, the volume of gas produced or the mass lost over time.
58
compromise
balancing several different factors in order to get the best possible outcome. In industry, the position of the equilibrium and rate of reaction must be considered when deciding the conditions for the reaction. These factors must also be balanced with safety and economics
59
dynamic equilibrium
a closed system in which the rates of the forward and reverse reactions are equivalent. The concentrations of reactants and products don’t change
60
le chatelier's principle
when a system in dynamic equilibrium is subject to change, the position of equilibrium will shift to minimise the change. This principle is used to determine the effect of changing pressure, temperature or concentration on the position of equilibrium
61
kc
the equilibrium constant that is equal to the concentration of products raised to their stoichiometric coefficients divided by the concentration of reactants to the power of their stoichiometric coefficients. When KC is greater than 1, the equilibrium favours the products. When KC is less than 1, the equilibrium favours the reactants.

chem (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions