Naming Of Compounds Flashcards
What is the name for FeSO4 .7H2O?
Iron(ll) tetraoxosulphate(VI) heptahydrate
What is the name for Na2CO3 . 10H2O?
Sodium trioxocarbonate (IV) decahydrate
How are double salts named?
All cations are named first in alphabetical order, except hydrogen is placed last, then all anions in alphabetical order
What is the name for AlNH4 (SO4)2*12H2O?
Aluminium ammonium bis tetraoxosulphate (VI) deodecahydrate
How are basic salts named?
All cations are named first in alphabetical order, followed by all anions also in alphabetical order
What are acid salts?
Salts containing replaceable hydrogen atom(s) due to incomplete neutralization of a polyprotic acid
What is the molecular formula?
A formula that shows the actual whole number of different atoms present in a molecule of the compound
What is empirical formula?
A formula that shows the simplest whole number ratio of different atoms in one molecule of a compound
What is quantitative analysis?
An analysis that determines the mass, especially the percentage by mass of the different elements present in a compound
What is the structural formula?
A formula that shows how atoms in a molecule or units are bonded to each other
What is the dashed structural formula or displayed formula?
A type of structural formula where the atoms and bonds are explicitly shown
What is the condensed structural formula?
A type of structural formula where atoms are written down in a list-like format
What is the skeletal structural formula used for?
It is normally used for hydrocarbons and represents atoms as line segments
What is the molecular formula of a compound with C6H14 as its molecular formula?
The empirical formula of C3H7
What is the purpose of qualitative analysis?
To determine the different types of elements, ions, or functional groups present in a compound/species
What is a combination or synthesis reaction?
A combination or synthesis reaction is a reaction between two or more substances to produce just one product.
Give an example of a synthesis reaction.
Fe(s) + S(s) → FeS(s) and 2N2 + 3H2 → 2NH3
Define decomposition reaction.
A decomposition reaction is a reaction in which one reactant breaks down to give two or more simpler products, often under the effect of heat.
What are the three ways decomposition reactions may be caused?
Decomposition may be caused by heat (thermal decomposition), by light (photo decomposition), or by electrolysis (electrolytic decomposition).
Give an example of a thermal decomposition reaction.
MgCO3(s) → MgO(s) + CO2(g)
What is double decomposition?
Double decomposition is a reaction in which two compounds react to form two new compounds by an exchange of ions.
What is a precipitation reaction?
A precipitation reaction is a reaction between two solutions to form an insoluble product.
Give an example of a precipitation reaction.
Pb(NO3)2(aq) + 2NaCl(aq) → PbCl2(s) + 2NaNO3(aq)
What is a neutralization reaction?
A neutralization reaction is a reaction between an acid and a base to produce water and a salt.
What is oxidation and reduction in a redox reaction?
Oxidation is the addition of oxygen to a substance, while reduction is the removal of oxygen.
What is the name of the compound Na2S203?
The compound Na2S203 is called sodium trioxothiosulphate (VI).
How is the oxidation state calculated for one of the sulphur atoms in Na2S203?
The oxidation state is calculated with one of the sulphur atoms considered as if it is oxygen. The equation is y + 4(-2) = -2, which gives y = +6.
What is the name of the compound S2O82-?
The compound S2O82- is called hexaoxo - µ- peroxodisulphate (VI) ion. ‘Per’ is used due to the —0-0— linkage.
How are acids containing oxygen (oxo acids/ternary acids) named?
Acids containing oxygen are named by first naming the number of oxygen atoms as ‘oxo,’ ‘dioxo,’ etc. depending on the number of oxygen atoms present. Then, the central atom is named with its oxidation state in brackets, followed by the word ‘acid.’
Give an example of a binary acid and its naming process.
An example of a binary acid is HCI. The element’s root name is ‘chlorine,’ and the last three letters ‘-ine’ are replaced with ‘-ic.’ Finally, the word ‘acid’ is added. The name is ‘Hydrochloric acid.’
How are bases named?
Bases are named as binary compounds with the oxidation number put in brackets in Roman numerals, if it varies. For example, Fe203 is named ‘Iron (III) oxide.’
How are normal salts named?
Normal salts are named by first naming the cation, followed by its oxidation number if it varies. Then, the acid radical is named as if it is an oxo anion. The name of the central atom has its last two or three letters removed and ‘-ate’ added.
What is the definition of a hydrate?
A hydrate is an ionic compound in which the formula unit includes a fixed number of water molecules together with cations and anions.
What is the oxidation number or oxidation state of an atom?
The oxidation number or oxidation state of an atom is the real or hypothetical/assumed charge an atom carries in its pure state or in a compound based on given rules.
How are oxidation numbers determined?
Oxidation numbers are assigned according to specific rules, such as the oxidation number of free neutral atoms in uncombined elements is zero.
What is an ionic charge?
An ionic charge is the positive or negative charge on an atom, represented by the difference between the number of protons and electrons.
How are oxidation numbers used in naming inorganic compounds?
Oxidation numbers are used in naming inorganic compounds as they provide information about the charge of individual atoms in the compound.
What is the oxidation state of oxygen in most compounds?
In most compounds, oxygen has an oxidation state of -2, except in specific cases like peroxides and superoxides.
What is the oxidation number of hydrogen in all compounds?
The oxidation number of hydrogen in all compounds is +1, except in metal hydrides where it is -1.
When are more electronegative atoms assigned negative charges in covalent compounds?
In covalent compounds, the more electronegative atom is assigned a negative charge to reflect its higher electronegativity.
What are some examples of elements with fixed oxidation states?
Examples of elements with fixed oxidation states include elements in groups 1 and 2 having +1 and +2 respectively, and aluminium having +3.
What is the condensed structure of C6H14?
CH3CH2CH2CH2CH2CH3
What is the structure of hydrogen peroxide (H2O2)?
H-O-O-H
What is the aim of the experiment to determine the empirical formula of magnesium oxide?
To determine the empirical formula of magnesium oxide by heating magnesium in oxygen.
What equation represents the reaction between magnesium and oxygen in the experiment?
Mg(s) + O2(g) → MgxOy(s)
What precautions should be taken during the experiment?
- Ensure that the magnesium burns completely by weighing to constant mass. 2. Ensure that none of the oxide is lost during the experiment by covering the crucible with a lid. 3. Wear safety goggles to protect your eyes from the flame.
Why is water added in the experiment?
Water is added to convert any Mg3N2 formed to MgO.
What is the empirical formula of magnesium oxide?
MgO
What are the four laws of chemical combinations?
The four laws of chemical combinations are: 1. The law of constant composition (law of definite proportion or constant proportion),
- The law of multiple proportion,
- The law of conservation of matter/mass, and
- The law of reciprocal proportion (law of equivalent proportion).
What is dissociation reaction?
Dissociation reaction is the breaking up of a compound into simpler forms through reversible reactions especially under the influence of heat and of pressure.
Give an example of a dissociation reaction.
i) N2O4(g) → 2NO2(g) (ii) NH4Cl(s) → NH3(g) + HCl
How can dissociation also occur?
Dissociation may also be in terms of an ionic substance breaking into component ions in solution or the decomposition of a molecule into single atoms.
What is meant by the term ‘dissociation’ when referring to acids?
An acid breaking down into ions in solution is also termed dissociation.
Write the dissociation reaction of HCl in solution.
HCl(aq) → H+(aq) + Cl-(aq)
What are the possible outcomes of the types of reactions mentioned?
All the types of reactions studied above may result in the absorption of heat (endothermic reactions) or in the release of heat (exothermic reactions).
What is catalysis?
Catalysis is a reaction in which the rate of reaction is changed by a catalyst.
Provide an example of a catalytic reaction.
An example is in the preparation of oxygen gas. Equation: 2H2O2 — 2H2O+O2 Manganese (IV) oxide, MnO2 is the catalyst.
What is the law of constant composition also known as?
The law of definite proportion
What does the law of constant composition state?
Pure samples of the same chemical compound contain the same elements combined in the same proportion by mass.
How can the law of constant composition be verified?
By preparing two different samples of copper (II) oxides using different methods and analyzing the masses of copper and oxygen.
What is reduction reaction in the context of this experiment?
The loss of oxygen from a substance.
What is the law of multiple proportion?
The law of multiple proportion states that when two or more different compounds of the same two elements are compared, the masses of one element that combines with a fixed mass of the second element are in a ratio of small whole numbers.
Give an example of the law of multiple proportion.
If 1g of an oxide combines with 0.5g of another element, and 2g of another oxide combines with 1g of the same element, the ratio is 2:1.
What is the name of the ion with the formula N3-?
Azide ion
What is the oxidation state of hydrogen?
+1
What is the oxidation state of oxygen in most of its compounds?
-2
Which elements have variable oxidation states?
All elements above atomic number 20, carbon, nitrogen, sulphur, silicon, phosphorus, and the halogens
What is the compound with the formula Al203 called?
Aluminium oxide
How do you name an anion containing oxygen bonded to a central atom?
Mention the number of oxygen atoms as oxo, dioxo, trioxo, or tetraoxo, replace the last two or three letters of the name of the central atom with -ate, and add the word ion
What is the name of the ion with the formula NO3-?
Trioxonitrate (V) ion
According to the law of conservation of mass, what can neither be created nor destroyed in a chemical reaction?
Matter
What is the compound with the formula S2032- called?
Trioxothiosulphate (VI) ion
What is the mass of oxygen in the first sample?
0.2g
What does a white precipitate indicate in a chemical reaction?
The formation of an insoluble solid
What is the ratio of the masses of copper in the two samples?
1:2
What is the purpose of the cork in the experiment to verify the law of conservation of matter?
To prevent the exchange of matter between the system and surroundings
What does a chemical equation represent?
The elements, compounds, and products involved in a chemical reaction
How do we balance a chemical equation?
By introducing appropriate coefficients to ensure no atoms are created or destroyed
What does an unbalanced equation imply?
Atoms have been created or destroyed
USES OF OXIDATION NUMBERS
(a) Oxidation numbers are used in naming inorganic compounds.
(b) It can also be used in identifying oxidizing and reducing agents in redox reactions.
IONIC CHARGE
It is the positive or negative charge on an atom, which is represented by the difference between the number of protons and electrons. It can also be the net charge on a polyatomic ion.
