| 1 |
A free radical reaction takes place in three steps, initiation, propagation and terminations. Which of the following expression represents a propagation step |
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| 2 |
In a heterollytic bond fission reaction |
A molecule of H<sub>2</sub>O is formed
A molecule of H<sub>2</sub>O is eliminated
A free radical is formed
A positive and a negative ion is formed
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| 3 |
Which of the following expressions show a heterolytic bond fission |
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| 4 |
Which reaction produces a free radical |
SN reaction
Homelytic fission reaction
Heterolytic fission reaction
Addition reaction
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| 5 |
Which statement is true about a free radical |
An atom with a positive charge
An atom with a negative charge
An atom with a lone pair of electrons
An atom with unpaired electron
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| 6 |
A transition element is defined as an element of 3d series |
Which is metal
Which has one stable ion
Which has two stable ions
Which has at least one stable ion with incomplete d-orbital
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| 7 |
Which element has 4 unpaired electrons in 3d-orbital |
Chromium - 24
Manganese - 25
Iron - 26
Cobalt - 27
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| 8 |
Which is the correct electronic configuration of Cr - 24 |
1s<sup>2</sup>, 2s<sup>2</sup>, 2p<sup>6</sup>, 3s<sup>2</sup>, 3p<sup>6</sup>, 3d<sup>4</sup>, 4s<sup>2</sup>
1s<sup>2</sup>, 2s<sup>2</sup>, 2p<sup>6</sup>, 3s<sup>2</sup>, 3p<sup>6</sup>, 3d<sup>3</sup>, 4s<sup>2</sup>, 4p<sup>1</sup>
1s<sup>2</sup>, 2s<sup>2</sup>, 2p<sup>6</sup>, 3s<sup>2</sup>, 3p<sup>6</sup>, 3d<sup>5</sup>, 4s<sup>1</sup>
1s<sup>2</sup>, 2s<sup>2</sup>, 2p<sup>6</sup>, 3s<sup>2</sup>, 3p<sup>6</sup>, 3d<sup>5</sup>, 4p<sup>1</sup>
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| 9 |
Transition elements differ from s and p block elements due to their characteristic properties. What is not he characteristic property of transition elements |
Transition elements show variable oxidation states
Their salts are coloured
They can be used as catalyst
All of them are metals
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| 10 |
Potassium ferrocyanide is a |
Mixed salt
Double salt
Complex salt
Normal salt
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| 11 |
Which alloy contains 50% copper, 25% zinc and 25% nickel |
German silver
Gun metal
Bell metal
Brass
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| 12 |
Bronze is an alloy which contains |
60% cu
70% cu
80% cu
99% cu
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| 13 |
Transition elements form which type of bond |
Ionic bonds only
Covalent bonds only
Ionic and covalent bonds
Polar bonds
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| 14 |
E.D.T.A is |
Mono-dentate
Bi-dentate
Polydentate
Having three lone pairs of electrons
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| 15 |
In physical and chemical properties, transition elements show |
Similarities
Dissimilarities
Both of these
Somestimes similarities, sometimes dissimilarities
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| 16 |
The elements in which d or f-orbitals are incomplete are called |
Transition elements
Typical elements
Actinides
lanthanides
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| 17 |
What are alloys |
A homogenous mixture of two or more elements
A homohenous mixture of metal and a non-metal
A homogenous mixture of two or more metals
None of the above
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| 18 |
Elements in which f-orbitals are in the process of completion are called |
Outer transition element
Inner transition elements
Non-tranistion elements
Radioactive elements
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| 19 |
Which one of the following has highest density |
Zn
Os
Ni
Cu
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| 20 |
The total number of transition elements is |
10
14
40
50
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| 21 |
Coordination number of Pt in [Pt Cl(NO2) (NH3)]2-is |
2-
4
1
6
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| 22 |
The colour of transition metal complexes is due to |
d-d transitions of electrons
Para magnetic nature of transition elements
Ionization
Loss of s-electrons
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| 23 |
Which of the following is a not typical transition element |
Cr
Mn
Zn
Fe
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| 24 |
An oxidixing agent |
K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub>
H<sub>2</sub>SO<sub>4</sub>
FeSO<sub>4</sub>
K<sub>2</sub>SO<sub>4</sub>
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| 25 |
Potassium chromate has formula |
KClO<sub>3</sub>
K<sub>2</sub>CO<sub>3</sub>
K<sub>2</sub>CrO<sub>4</sub>
K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub>
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| 26 |
Calcium carbide reacts with water to produce |
Acetylene
Methane
Ethylene
Ethane
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| 27 |
Where lime is not used |
In refining or metals
In paper industry
In glass industry
In the preparation of NaOH
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| 28 |
Lime, calcium oxide, is used in agriculture for |
Adding ca metal in soil
Making soil acidic
Neutralizing acidic soil
Adding oxygen to soil
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| 29 |
Plaster of pares is obtained by heating |
Gypsum
Epsom
Lime stone
Dolomite
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| 30 |
Gypsum is applied to the soil to provide calcium and |
Oxygen
Nitrogen
Phosphorous
Sulphur
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