24/25/26/28/29/30/31/32/36/37 Flashcards
1
Q
What type of substance is sulfric acid
A
Corrosive
2
Q
What type of acid is in car batteries?
A
Sulfric acid
3
Q
What type of acid is in vinegar?
A
Acetic acid
4
Q
What type of acid is in fizzy drinks?
A
Carbonic acid
5
Q
What type of acid is in vitamin C?
A
Ascorbic acid
6
Q
What type of acid is in the stomach?
A
Hydrochloric acid
7
Q
What type of acid is in nettle and ant stings?
A
Formic acid
8
Q
What type of acid is in lemons and grapefruits
A
Citric acid
9
Q
What type of acid is in sour milk
A
Lactic acid
10
Q
What effect does an acid have on litmus
A
Acids turn litmus from blue to red
11
Q
What affect do bases have on litmus?
A
Bases turn litmus from red to blue
12
Q
What base does drain cleaner contain?
A
Caustic soda (sodium hydroxide)
13
Q
What base does indigestion tablets contain?
A
Magnesium hydroxide
14
Q
What base does window cleaner contain?
A
Ammonia solution
15
Q
Define indicator
A
An indicator shows by means of a colour change whether a substance is acidic or basic
16
Q
What is a neutral substance
A
A substance that has no effect on litmus and therefore is neither an acid or a base (pH of 7)
17
Q
Give two examples of indicators
A
- litmus (paper/solution)
- methyl orange
18
Q
What is the pH scale ?
A
The scale that measures the level of acidity or basicity of a substance
19
Q
Acids have a pH of …. ?
A
Less than 7
20
Q
Alkalis have a pH of …. ?
A
More than 7
21
Q
What is an Alkali
A
A base that dissolves in water
22
Q
What is used to measure the pH of a substance
A
- pH sensor
- pH paper/universal indicator solution
23
Q
Give 3 examples of neutral substances
A
- distilled water
- blood
- milk
- saliva
24
Q
What is the composition of the air?
A
78% - nitrogen
21% - oxygen
1% - inert gases and carbon dioxide
25
What are inert gases
Unreactive gases
26
What two scientists discovered oxygen?
- joseph priestly
| - antoine lavoisier
27
What is the word equation for the preparation of oxygen?
Hydrogen peroxide + manganese dioxide ➡️ water + oxygen
28
What is the chemical equation for the preparation of oxygen?
2H2O2 + Mn02 = 2H2O + O2
29
What is the catalyst in the preparation of oxygen?
Manganese dioxide
30
What is a catalyst?
A catalyst is a substance that speeds up the rate of a chemical reaction but is not used up in the reaction itself
31
What are the physical properties of carbon dioxide?
- colourless, odourless, tasteless gas
- slightly soluble in water
- slightly heavier than air
32
What are the chemical properties of oxygen
- supports combustion
- reacts with most elements to form oxides
- no effect on litmus
33
What are the uses of oxygen?
- breathing
- burning and welding
- space rockets
34
What is the word equation for the preparation of carbon dioxide?
Calcium carbonate + hydrochloric acid ➡️ calcium chloride + water + carbon dioxide
35
What is the chemical equation for the preparation of carbon dioxide?
CaCO3 + 2HCl = CaCl2 + H20 + CO2
36
What are the physical properties of carbon dioxide?
- colourless, odourless, tasteless gas
- slightly soluble in water
- denser than air
37
What are the chemical properties of carbon dioxide?
- does not support combustion
- turns limewater milky
- dissolves in water to form carbon acid
38
What are the uses of carbon dioxide?
- fizzy drinks
- fire extinguishers
- refrigeration
- special effects on stage
39
Give two examples of common laboratory acids?
Hydrochloric acid - HCI
| Sulfric acid - H2SO4
40
Give two examples of common laboratory bases?
Sodium Hydroxide - NaOH
| Calcium hydroxide - Ca(OH)2
41
What are strong acids?
Strong acids produce a lot of hydrogen ions
42
What is neutralisation?
When an acid reacts with a base to form a neutral substance
43
What is a salt?
A salt is formed when the hydrogen in an acid is replaced by a metal
Acid + base ➡️ Salt + Water
44
Give an example of a salt?
Hydrochloric acid + sodium hydroxide = sodium chloride (+water)
HCI + NaOH = NaCl + H2O
45
What is titration?
The method of adding one solution from a burette to another solution in order to find out how much of the two solutions will just react with each other
46
What is a fuel?
Any substance that burns in oxygen to produce heat
47
Give examples of fuels (solids, liquids, gases)
Solids: coal, turf, wood
Liquids: petrol, diesel, paraffin oil
Gases: methane
48
How was coal formed?
Earth and rock compressing plant remains from millions of years ago
49
How was oil and natural gas formed?
Pressure of the earth on decaying remains
50
What are fossil fuels?
Fossil fuels are fuels that were formed from the remains of plant and animals that lived millions of years ago
51
What are hydrocarbons?
Fossil fuels contain hydrocarbons. Hydrocarbons are compounds consisting of hydrogen and carbon only
52
What is produced when hydrocarbons are burned?
Water and Carbon Dioxide
53
Fossil fuels + oxygen ➡️ ....
Fossil fuels + oxygen ➡️ carbon dioxide + water
54
What is acid rain?
Rain with a pH of about 5.5
55
How is acid rain made?
Sulfric and nitric acid dissolve in the rain
56
What are the affects of acid rain?
- destroys lakes, killing fish
- harms trees
- attacks stone and iron
57
What is an atom?
An atom is the smallest particle of an element which still retains the properties of that element
58
What is an electron?
An electron is sub-atomic particle of an atom with a negative charge. It is in the shell/orbit of the atom
59
What is a proton?
An proton is sub-atomic particle of an atom with a positive charge. It is in the nucleus of the atom
60
What is a neutron?
An proton is sub-atomic particle of an atom with no charge. It is in the nucleus of the atom
61
What does a.m.u. Stand for?
Atomic mass unit
62
Give the atomic mass unit for each of the sub atomic particles
Neutron : 1amu
Proton : 1amu
Electron : 1/1840 amu
63
Which Scientist discovered the orbits/ shells of the atom?
Neils Bohr
64
Define 'atomic number'
The atomic number of an atom is the number of protons in the nucleus of that atom
65
What is the mass number
Mass number = number of protons + number of neutrons
66
How is the number of neutrons found?
Number of neutrons = mass number - atomic number
67
What is the periodic table?
The periodic table is an arrangement of elements in order of increasing atomic number
68
What are the groups in the periodic table?
- vertical columns
- eight main groups
- each group has similar chemical properties
- same number of electrons in outer shell/orbit
69
What are the periods in the periodic table?
- horizontal rows
- seven periods
- labelled n=1, n=2 ect.
70
List the groups of the periodic table
```
Alkali metals
Alkaline earth metals
Transition metals
Halogens
Noble (inert) gases
```
71
What are isotopes?
Isotopes are atoms of the same element that have different numbers of neutrons
72
What is a molecule?
Molecule is a group of atoms joined together. It is the smallest particle of an element or compound that can exist independently
73
Elements that have eight electrons in their outer shell are .... ?
Very unreactive
74
State the octet rule?
When chemical bonding occurs, atoms try to have eight electrons in the outer orbit
75
What is a covalent bond?
A covalent bond is a bond that consists of shared electrons
76
What is a single covalent bond?
A single bond is formed when one pair of electrons is shared e.g the hydrogen molecule
77
What is a double covalent bond?
A double covalent bond is formed when two pairs of electrons are shared
78
What is an ion?
An ion is a charged atom or group of atoms
79
What is an ionic bond?
An ionic bond is the force of attraction between positive and negative ions in a compound eg sodium chloride
80
What is the formula for sodium chloride?
NaCI
81
What is the formula for magnesium oxide?
MgO
82
What is the formula for Iron sulfide?
FeS
83
What is the formula for calcium chloride?
CaCI2
84
What is the formula for calcium carbonate?
CaCO3
85
What is the formula for copper sulphate?
CuSO4
86
What is the formula for manganese dioxide?
MnO2
87
What is the formula for sodium hydroxide?
NaOH
88
What is the formula for Calcium hydroxide?
Ca(OH)2
89
What are the reactants?
Chemicals that react together in a chemical reaction
90
What is the products?
The substance formed as a result of the chemical reaction
91
What is a balanced equation?
A balanced equation is one in which the total number of atoms of each element on the left-hand side of the equation is equal to the total number of atoms on the right-hand side of the equation
92
What is a force?
A force is something that causes an object to accelerate
93
What is the unit of force?
Newton : N
94
How can force be measured?
Using a spring balance or newton-meter
95
What does weight do
Moves an object toward the centre of the earth
96
Friction
Slows objects moving over each other
97
Tension
Moves objects on pulleys or stops a body falling
98
What is weight
The weight of an object is the force of gravity on it
Pull slightly stronger at poles
Pull on the moon 1/6 of on earth
Deep in space objects have no pull - weightless
99
A) What is mass measured in
| B) what is weight measured in
A) kilograms
| B) newtons
100
Weight vs mass
Weight in newtons = mass in kilograms (times 10)
101
What is friction?
Friction is a force which opposes motion between two objects in contact
102
What is a lubricant?
A substance which reduces friction eg oil in a car engine
103
What happens an elastic when a force is put on them?
They change shape and when the force is removed they return to their original shape
104
What is hookes law?
The extension of a spring is directly proportional to the force that is stretching it
105
What is work?
Work done = force ✖️ distance moved (joule)
106
What is energy and what is it measured in?
Energy is the ability to do work (joule)
107
What is power and what is it measured in
Power is the work done per unit time
Power = work done ➗ time taken
(Watt)
108
How is the turning effect of a force increased?
- by increasing the size of the force itself
| - by increasing distance from the applied force to the fulcrum
109
What is the moment of a force ?
Measure of the turning effect of a force
= (force) ✖️ (perpendicular distance from the force to the fulcrum)
110
What is a lever?
A lever is any rigid body that is free to turn about a fixed point or axis called a fulcrum
111
Give 5 examples of levers
- scissors
- light-switch
- shovel
- tap
- oar
112
State the law of the lever
When a lever is balanced by any number of forces, she sum of the clockwise moment acting on it is equal to the sum of the anticlockwise moment
113
What is the centre of gravity
The centre of gravity of an object is the point through which the weight of the object appears to act
114
What is 'in equilibrium'?
An object that is balanced is said to be 'in equilibrium'
115
State factors which affect stability
- a low centre of gravity helps stability
| - a wide base helps stability
