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An important facility for 12th class students preparing for short questions chemistry 12th class chapter 6 of BISE. Get hundreds of questions to prepare and get better marks in 12th chemistry
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Our database contains a total of 0 questions for chemistry Short Questions. You’ll prepare using this huge databank.

Question: 1
Why d- block and f-block elements are called transition elements?
Answer: 1
1-33
d-block and f-block elements are called transition elements because they are located between the s and p block elements and their properties are in transition between the metallic elements of the s-block and nonmetallic of the p block.
Question: 2
What type of elements form substitution alloy and why?
Answer: 2
2-33
Owing to the similarity in the size of transition metals,some transition metal atoms are able to replace one another in the metallic lattice and from substitutional alloys among themselves,Alloy steel are important example of this type of material in which iron atoms are substituted by chromium,manganese and nickel atom.
Question: 3
Why Transition metals show variable valencies?
Answer: 3
3-33
Transition metals exhibit variable valence or oxidation states .They show variable valencies because of the involvement of the unpaired d electron to s electron in bond information.
Question: 4
What are the typical and non typical transition elements?
Answer: 4
4-33
In order to maintain a rational classification,the elements of group IIB and group IIIB are referred to as non-typical transition elements and the elements in the remaining transition series are called typical transition elements.
Question: 5
What are paramagnetic and Diamagnetic substance?
Answer: 5
5-33
Substance which are weakly attracted by a strong magnetic field are called paramagnetic substance.
Those substance which are weakly repelled by a strong magnetic field are called diamagnetic substance.
Question: 6
Explain d-d transmission?
Answer: 6
6-33
When d orbitals are involved in bonding,they split up into twip energy levels,one set has a higher energy that the other,The electron residing d orbitals.d orbital a part of the visible light and jump to high energy d orbitals,This process is called d-d transition.
Question: 7
What is the cause of paramagnetic behaviour?
Answer: 7
7-33
Paramagnetic behaviour is caused by the presence of unpaired electrons in an atom.molecule or ion because there is magnetic moment a associated with the spinning electrons,It increase with the increase in the number of unpaired electrons.
Question: 8
Define Ligand.
Answer: 8
8-33
The atom or ions or neutral molecules,which surrounded the central metal ion and donate electron pair to it called ligands.They must be anions or neutral molecules.
Question: 9
Define central metal atom or ion?
Answer: 9
9-33
A metal atom or ion surrounded by a number of ligands is called central metal atom or ion e,g Cu is the central. metal ion.
Question: 10
Give reason for the development of colours in the transition complexes?
Answer: 10
10-33
In transition example ,the d-orbits are responsible for the colour development in their compounds,When these orbitals are involved in bonding,they split up residing in low energy d orbitals absorb a part of the visible light and jump to the high energy d orbital,This process is called d-d transition.
Question: 11
Define substitutional alloy?Give an example.
Answer: 11
11-33
Due to the similarity in the sizes of transition metals,some transition metals atom are able to replace one another in the metallic lattice and from substitutional alloy among themselves,Alloy of steels are an important example of this of material in which iron atoms are substituted by chromium,manganese and nickel atom.
Question: 12
What are interstitial compound?
Answer: 12
12-33
When small non metal atom like H.B,C and N enter the interstices of transition metal and impart useful feature to them,they are called interstitial compound.
Question: 13
Write name of following complexes:
1.K2 (Cu(CN4))
Answer: 13
13-33
Names of K2 (Cu(CN4)) : Potassium tetracyanocuprate
Question: 14
What do you mean by Ligand and Coordination sphere?
Answer: 14
14-33
Ligand:The atom or ions or neutral molecules,which surrounded the central metal ion and donate electron pair to it called ligands.They must be anions or neutral molecules.
Coordination sphere: The central metal atom or ion along with ligand is called the coordination sphere,It is usually placed in square brackets.It may be anionic cationic or neutral.
Question: 15
How the entrapped gases are removed form the steel?
Answer: 15
15-33
In order to remove entrapped bubbles of gases such,as O2N2and Co2a little aluminum or ferro silicon is also added,Aluminium removes nitrogen as nitrate.
Question: 16
What are Chelate and what they contain?
Answer: 16
16-33
Chelate: When all the donor atoms of a polydentate ligand get coordinated with the same metal ion,a complex is formed which contain one or more rings in its structure and hence is called Chelate.
Question: 17
Define coordination number.
Answer: 17
17-33
The number of lone pair of electrons provided by the ligand to the central metal atom or ion is called the coordination number of the central metal atom or ion.
Question: 18
What is meat by Coordination sphere ?
Answer: 18
18-33
The central metal atom or ion along with ligands is called the coordination sphere,It is usually placed in square brackets ,It may be anionic cationic or neutral.
Question: 19
Why does damaged tin plated iron get rusted quickly?
Answer: 19
19-33
If the protective coating is damaged ,then iron comes into contact with moisture,A galvanic cell is established in which tin acts as cathode and iron as an anode,The electrons flow from iron to tin,where they discharge H+ions,leaving behind OH- in the solution,These hydroxide ions reacts with iron forming which dissolves rapidly in water,From this it can be concluded that plated iron gets rust more rapidly when the protective coating is damaged than the non-plated iron.
Question: 20
Write down the chemical formulas of
1.Magnetite
2.Haematite

Answer: 20
20-33
Formula of Magnetite: Fe3O4
Formula of Haematite : Fe2O3
Question: 21
What is medium carbon steel.Also write its uses.
Answer: 21
21-33
Medium carbon steel contains 0.2-0.7% Carbon,It is harder than mild steel,It is also malleable and ductile,It is used in making rails ,axles,castings.
Question: 22
Define Corrosion?
Answer: 22
22-33
Any process of chemical decay of metal is due to the action of surrounding medium is called corrosion.
Question: 23
What are Chelates?
Answer: 23
23-33
When all the donor atoms of a polydentate ligand get coordinated with the same metal ion,a complex is formed which contain one or more rings in its structure and hence is called Chelate,
Question: 24
Name different forms of iron and which is the purest.
Answer: 24
24-33
Pig iron or case iron : 2.5 to 4.5% Carbon
Wrought iron: 0.12 to 0.25 carbon
Steel : 0.25 - 2.5% Carbon
Purest form of iron is Wrought iron.
Question: 25
Write two uses ofK2Cr2O7.
Answer: 25
25-33
  1. K2Cr2O7finds extensive use in dyeing,
  2. It is used in leather industries for chrome tanning.
Question: 26
Give reason that M.P and B.P show maximum value of the middle of 1st transition series.
Answer: 26
26-33
M.P and B.P show maximum of the middle of 1st transition series and then decrease to a minimum level at the end of the series,This trend in M.P correlates well with the strength of binding force.
Question: 27
How chromate ions are converted into dichromate ions?
Answer: 27
27-33
Chromate and dichromate ions exist in equilibrium as :
CrO4-2+2H+--------- Cr2O7-2+H2O
On adding the equilibrium will shift towards right and chromate ions will converted into dichromate ions.
Question: 28
What is Tin Plating ?
Answer: 28
28-33
The process of tin plating consists of dipping the clean sheet of iron in a bath of molten tin and then passing it through hot pair of roller.
Question: 29
Define Sacrificial corrosion.
Answer: 29
29-33
If a protective layer of zinc is damaged a galvanic cell is established in the presence of moisture,Iron serves as a cathode and zinc as an anode,Electrons flow from zinc to iron as a result of which Zn decays while Fe remains intact,This is called sacrificial corrosion.
Question: 30
How does process of galvanizing protect iron from rusting?
Answer: 30
30-33
Galvanizing is done by dipping a sheet of iron in zinc chloride solution and heating,The iron sheet is then removed,rolled into zinc bath and then cooled,In this case it a protective layer of zinc is damages a galvanic cell is established in the presence of moisture,Iron serves as cathode and zinc serve as anode. Electron flow from zinc to iron ,as a result of which Zn decays while Fe remains intact,This is called sacrificial corrosion,This is the way galvanizing helps protecting iron from rust.
Question: 31
Define paramagnetic?Which two transition metal ions have strongest paramagnetic behaviour.
Answer: 31
31-33
The substance which are weakly attracted by a strong magnetic field are called paramagnetic For example Fe2+ and Mn3+.
Question: 32
Give two use of KMnO4.
Answer: 32
32-33
  1. It is used as an oxidizing agent.
  2. It is used as disinfectant and germicide.
  3. It is used in manufacturing of many organic compounds.
Question: 33
Explain chromyl chloride.
Answer: 33
33-33
When solid potassium dichromate is heated with solid metal chloride in the presence of concentrated sulphuric acid chromyl chloride is produced.