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The given figure depicts the atomic structure of an atom of an element ‘X’. Write the following information about the element ‘X’
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0
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16960
|
March 20, 2018
|
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Show diagrammatically the electron distribution in a sodium atom and a sodium ion and also give their atomic number
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0
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5100
|
March 20, 2018
|
|
The ratio of the radii of hydrogen atom and its nucleus is ~10^5
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0
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2810
|
March 20, 2018
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What are the postulates of Bohr’s model of an atom?
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0
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7419
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March 20, 2018
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In what way is the Rutherford’s atomic model different from that of Thomson’s atomic mode
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0
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1547
|
March 20, 2018
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What is the gold foil experiment?
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0
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8538
|
March 20, 2018
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State the method of determining the valency of an element if its atomic number is given
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0
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3727
|
March 20, 2018
|
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Write the formula of the compounds formed by the following ions. Mg2+ and S2- Cu2+ and OH-
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0
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19348
|
March 20, 2018
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Write the molecular formulae of all the compounds that can be formed by the combination of following ions
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0
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763
|
March 20, 2018
|
|
Write the molecular formulae for the following compounds:
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0
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726
|
March 20, 2018
|
|
. What information do you get from the figures about the atomic number, valency of atoms X, Y and Z? Give your answer in a tabular form
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0
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1080
|
March 20, 2018
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How many protons, neutrons and electrons are there in one atom of this radon isotope?
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0
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2299
|
March 20, 2018
|
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In the atom of an element ‘Z’, 5 electrons are present in the outermost shell
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0
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8885
|
March 20, 2018
|
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Complete the table on the basis of information available in the symbols given below
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0
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1523
|
March 20, 2018
|
|
The atomic number of lithium is 3. Its mass number is 7
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0
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5783
|
March 20, 2018
|
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An element ‘X’ contains 6 electrons in ‘M’ shell as valence electrons:
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0
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8936
|
March 20, 2018
|
|
Predict the valency of the following elements
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0
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5909
|
March 20, 2018
|
|
In the gold foil experiment of Geiger and Marsden, that paved the way for Rutherford’s model of an atom, ~ 1.00% of the alpha-particles were found to deflect at angles > 50°
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0
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2303
|
March 20, 2018
|
|
List any three distinguishing features between the models of an atom proposed by J.J. Thomson and Ernest Rutherford
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0
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4362
|
March 20, 2018
|
|
An element ‘Z’ forms the following compound when it reacts with hydrogen, chlorine, oxygen and phosphorous
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0
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7885
|
March 20, 2018
|
|
An element ‘X’ has a valency 3(+):
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0
|
5348
|
March 20, 2018
|
|
Why do isotopes show similar chemical properties
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|
0
|
712
|
March 20, 2018
|
|
Calculate the number of neutrons present in the nucleus of an element X
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0
|
1135
|
March 20, 2018
|
|
Identify the Na+ ion from the following figures. What is the valency of sodium atom? Give reason
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0
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8746
|
March 20, 2018
|
|
Find out the valency of the atoms represented by the Figs, (a) and (b)
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0
|
1118
|
March 20, 2018
|
|
Helium atom has 2 electrons in its valence shell but its valency is not 2. Explain
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0
|
1780
|
March 20, 2018
|
|
Why do helium, neon and argon have a zero valency?
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0
|
9098
|
March 20, 2018
|
|
Define valence electrons. Which electrons of an atom are involved in the chemical bond formation with other atoms?
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0
|
3475
|
March 20, 2018
|
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Write down the electron distribution of chlorine atom
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0
|
2283
|
March 20, 2018
|
|
The atomic number of Al and Cl are 13 and 17, respectively. What will be the number of electrons in Al3+ and Cl-?
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0
|
2214
|
March 20, 2018
|