The lightest as is:
- $N_2$
- $ Ar $
- $ Rn $
- $ He $
The Correct Option is D
Solution and Explanation
Top Questions on position of hydrogen in the periodic table
- The ionisation of hydrogen atom would give rise to
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Questions Asked in Rajasthan PMT exam
- 300 cal of heat is supplied to raise the temperature of 50 g of air from $ 20{}^\circ C $ to $ 30{}^\circ C $ without any change in its volume. Change in internal energy per gram of air is
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- Block A of mass 4 kg and block B of mass 6 kg are resting on a horizontal surface as shown in the figure. There is no friction between the block B and the horizontal surface. The coefficient of friction between the blocks is 0.2. If the value of $ g=10\,m/{{s}^{2}}, $ the maximum horizontal force F that can be applied on block B without any relative motion between A and B is
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Concepts Used:
Position of Hydrogen in the Periodic Table
In the periodic table, there is no fixed position of hydrogen. In some tables, the element ‘hydrogen’ is placed lonely at the top, and in some other tables, it is placed in the company of alkali metals.
The electronic configuration of hydrogen is 1s1 so by rule, it has to be placed in the first position. Hydrogen relates alkali metals in its electronic configuration. Hydrogen is also to be placed in the company of alkali metals because it just requires a loss of electrons to form an H+ ion just like other alkali metals. Although, hydrogen is also very similar to halogens as it can also gain one electron to achieve a noble gas configuration. Due to this problem of resembling alkali metals and halogens, the position of hydrogen is yet not fixed but it is conventionally placed on the top of the table.
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