General Chemical Skills Flashcards
(98 cards)
0
Q
Define atom.
A
The smallest electrically neutral particle of an element that can take part in chemical change.
1
Q
Define ion
A
An atom or group of atoms, which carries an electrical charge.
2
Q
Define relative atomic mass
A
The ratio of the average mass of one atom of an element to one twelfth of the mass of an atom of carbon 12
3
Q
Define compound
A
A substance formed when two or more chemical elements are chemically bonded together.
4
Q
Define molecule.
A
The smallest electrically neutral particle of an element or compound that can exist on its own.
5
Q
Define Avogadro’s number.
A
It is equal to 6.02 X 10^23 and it is the number of the carbon atoms to be found in 12 grams of carbon twelve
6
Q
Define relative formula mass
A
The sum of the masses of the elements in the formula or compound
7
Q
What does a I, II or III mean about the charge of an ion?
A
It is a +1 +2 or +3 charge.
8
Q
What does an element ending with ide mean. E.g. Nitride, chloride
A
It is just the element.
9
Q
What is the charge of phosphate?
A
-3
10
Q
What does a V, VI or VII mean?
A
A -3, -2 or -1 charge
11
Q
What is the equation of phosphate?
A
PO(4)
12
Q
What does -ate mean at the end of an element? E.g. Chlorate, sulphate or carbonate?
A
Bonded with oxygen.
13
Q
What is the charge of sulphate?
A
-2
14
Q
What is the equation of sulphate ?
A
SO(4)
15
Q
What is the equation of carbonate?
A
CO(3)
16
Q
What is the charge of carbonate ?
A
-2
17
Q
What is the charge of hydroxide?
A
-1
18
Q
What is the equation of hydroxide ?
A
OH
19
Q
What is the charge of nitrate?
A
-1
20
Q
What is the equation of nitrate?
A
NO(3)
21
Q
What is the charge of chlorate ?
A
-1
22
Q
What is the equation of chlorate?
A
Cl O(3)
23
Q
What is the charge of bromate?
A
-1
24
What is the equation of bromate ?
BrO(3)
25
What is the charge of iodate?
-1
26
What is the equation of iodate?
IO(3)
27
What is the charge of hydrogen carbonate?
-1
28
What is the equation of hydrogen carbonate?
HCO(3)
29
What is the equation for ammonium ?
NH(4)
30
What does mono or di hydrate mean?
It means a number of water molecules.
| If you ever have it in an equation, put a . and the number of water molecules. E.g. .4H(2)O
31
What is the equation of hydrochloric acid?
HcL
32
What is the equation of nitric acid?
HNO(3)
33
What is the equation of phosphoric acid?
H(3)PO(4)
34
What is the equation of carbonic acid?
H(2)CO(3)
35
What is the equation of ethanoic acid?
CH(3)COOH
36
Are compounds containing group 1 elements soluble or insoluble?
Soluble
37
Are ammonium salts soluble or insoluble?
Soluble
38
Are nitrate salts soluble or insoluble?
Soluble
39
Are chlorate salts soluble or insoluble?
Soluble
40
Are chloride, bromide and iodine salts soluble or insoluble?
Soluble apart from the ones containing Ag+, Pb2+ and Hg(2)2+ ions
41
Yes apart from the ones containing Ag+, Pb2+ and Hg(2)2+ ions
Are chloride, bromide and iodine salts soluble or insoluble?
42
Are sulphate compounds soluble?
Yes apart from Ba2+ , Sr2+ , Ca2+, Pb2+ and Hg2+ ions
43
Yes apart from Ba2+ , Sr2+ , Ca2+, Pb2+ and Hg2+ ions
Are sulphate compounds soluble?
44
Are hydroxide compounds soluble ?
No, apart from the ones containing group one metals and Ba2+ Ca2+ and Sr2+ ions
45
No, apart from the ones containing group one metals and Ba2+ Ca2+ and Sr2+ ions
Are hydroxide compounds soluble ?
46
Are sulfide compounds insoluble or soluble ?
Insoluble apart from ones containing group one and group two metals.
47
What is one ppm?
1 mg (0.001g) per kilogram
1g per metric tonne.
It is also 0.0001% and 10000ppm is 1%
48
What is the test for ammonium gas?
Get damp red litmus paper and it will then blue.
49
What is the test for Cl"2" , SO"2" and NO"2"?
It turns damp blue litmus paper, red then is bleaches it.
50
Define redox reaction.
Reduction and oxidation occur simultaneously. By exchanging electrons
51
Define displacement reaction.
Where entities are exchanged.
52
Define neutralisation reaction.
Interaction of protons and hydroxide ions to form water.
53
What is the chemical test for water?
CoCl"2" paper will turn white to blue.
54
What is an isotope?
Atoms with the same number of protons but a different number of neutrons.
55
What is relative isotopic mass?
It is the mass of an atom of an isotope of an element relative to mass of the mass of an isotope of carbon 12
56
How is the number of moles found with the number of particles?
No. Of moles= number of particles you have
| Number of particles in a mole
57
What is the molar mass?
The mass of one mole of something. It is measured in grams.
58
What is 1 dm cubed?
1 litre or 1000 cm cubed.
59
What is the equation linking moles, mass and molar mass?
Number of moles = mass / Molar mass
60
How is the molecular formula found from the empirical formula and the mass?
Divide the true mass by the empirical mass and then multiply the result by the empirical formula.
61
A chemical has a formula of C"4"H"3"O"2" and a molecular mass of 166g. Find the molecular formula.
The empirical mass is 83.
166/83 is 2.
Multiply the empirical mass by 2 giving, C"8"H"6"O"4"
62
When a hydrocarbon is burnt with an excess of oxygen, 4.4 g of carbon dioxide and 1.8 g of water are made. What is the empirical mass of the hydrocarbon?
When calculated, there are 0.1 moles of hydrogen and CO2 produced.
This means there are 0.1 moles of carbon and 0.2 moles of hydrogen.
This means the C:H ratio is 0.1:0.2 so the molecular formula is CH"2"
63
what is room temperature and pressure?
298 K and 101300 Pa
64
What is the volume occupied by 1 mole of gas at r.t.p?
24dm cubed.
65
How may moles are there in 6 dm cubed of oxygen gas?
6/24 = 0.25 moles.
66
How can the number of moles be calculated from the volume of the gas?
Number of moles = volume cm³
| 24000
67
What is a double salt?
It contains 2 cations or anions.
68
What is atom economy?
Molecular mass of desired product ÷ sum of molecular masses of all products X 100
69
What reactions have an atom economy of 100%?
Addition reactions as only one product is formed and this is the useful one.
70
Are carbonate salts soluble ?
No apart from the group one ions.
71
What is a spectator ion?
Species that don't change state and aren't included in ionic equations.
72
What is the gas constant ?
8.31 JK^-1 K^-1
73
What is the equation for gases and pressure ?
```
PV=nRT
Pressure NM²
Volume DM³
No of moles
Gas constant.
Temperature, (K)
```
74
What are the general trends on heating nitrates?
Generally the metal oxide, brown fumes of NO₂ and O₂ gas are produced.
For group one metals that aren't lithium, no NO₂ is produced.
The further down the table, the more energy is needed.
75
What is the general trend on heating carbonates ?
CO₂ and the metal oxide will be produced.
This won't work with group 1 metals other than lithium as bunson burners won't reach those temperatures.
The lower down, the greater the energy needed.
76
What are the 3 definitions of oxidation?
The loss of electrons.
The loss of hydrogen
The gain of oxygen.
77
What metals will acids react with?
Ones less reactive than hydrogen.
78
What happens when acid is mixed with water ?
They will fall apart to form positive hydrogen ions and the rest of the acid will form a negative ion.
79
What happens when CoCl₂∙6H₂O is heated?
It is a purple powder. When heated water vapour is produced and blue CoCl₂ is produced. It can dissolve in its own water
80
Explain the thermal decomposition of Cu(NO₃)₂∙2H₂O
The blue powder will emit water vapour. Oxygen gas will also be emitted. Nitrogen oxide will also be produced. The end result is black copper oxide.
81
Explain the thermal decomposition of NaNO₃
It is a white powder to start. It will melt and then oxygen gas will bubble through it.
82
Explain the thermal decomposition of ZnCO₃.
It begin with it is a white powder. This will decompose to zinc oxide. This is yellow while hot but white when cool.
CO₂ gas is also produced.
83
What does isoelectric mean?
A pair of ions will be isoelectric if they have the same no.of electrons.
84
What is a hydride?
A single type of atom bonded to hydrogen. NH₃ is a hydride.
85
When you have copper sulfate-5-water in solution and you are boiling it to form crystals, how do you know when to stop?
As you heat, put a glass rod into the solution. If when you take it out, I t has crystals on it, stop boiling.
86
What are cations and anions?
Anions are negative while cations are positive.
87
What is the charge of ammonium?
+1
88
What is the charge of a silver ion?
1 plus
89
If you were to spill acid, what do you do?
Rinse with lots of water. Add some hydrogen carbonate and mop up
90
What is a functional group?
Part of the molecule which determines how it will react/ group of atoms responsible for chemical properties.
91
What is the difference between hazard and risk?
A hazard is something that could cause harm e.g. fire a murderer.
A risk is the likely hood that someone could be harmed.
92
Define mole
the amount of any substance containing the same number of identical entities as there are in exactly 12 g of the carbon-12 isotope.
93
How does an acid become a salt?
The H⁺ ion is replaced by a metal or ammonium acid.
94
What is an alkali?
A soluble base that releases OH⁻ ions in aqueous solution.
95
Acid + base =
Salt and water.
96
Acid and carbonate=
Salt, water and carbon dioxide.
97
Acid and metal=
Salt and hydrogen.
