Noble metals like gold and platinum are soluble in which of the following mixtures?
- $1 : 1$ mixture of conc. $HNO_3$ and conc. $H_2SO_4$
- $1 : 3$ mixture of conc. $HCl$ and conc. $HNO_3$
- $1 : 3$ mixture of conc. $HNO_3$ and conc. $HCl$
- $1 : 3$ mixture of conc. $H_2SO_4$ and conc. $HCl$
The Correct Option is C
Solution and Explanation
Top Questions on Group 18 Elements
- Give below are two statements:
Statement-I : Noble gases have very high boiling points.
Statement-II: Noble gases are monoatomic gases. They are held together by strong dispersion forces. Because of this they are liquefied at very low temperature. Hence, they have very high boiling points.
In the light of the above statements, choose the correct answer from the options given below.- JEE Main - 2024
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- AP EAPCET - 2018
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Questions Asked in AP EAMCET exam
Which of the following are ambident nucleophiles?
[A.] CN$^{\,-}$
[B.] CH$_{3}$COO$^{\,-}$
[C.] NO$_{2}^{\,-}$
[D.] CH$_{3}$O$^{\,-}$
[E.] NH$_{3}$- AP EAMCET - 2024
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Identify the anomers from the following.
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The standard Gibbs free energy change \( \Delta G^\circ \) of a cell reaction is \(-301 { kJ/mol}\). What is \( E^\circ \) in volts?
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Concepts Used:
Group 18 Elements
The Group 18 elements, also known as noble gases except for Helium, are inert in nature because they have completely filled ns2 np6 electronic configuration in their valence shells. These gases also have high ionization enthalpy and more positive electron gain enthalpy. All these elements are chemically unreactive i.e. they don’t form many compounds.
Group 18 Elements consist of six elements. They are as mentioned below:
- Helium (He)
- Neon (Ne)
- Argon (Ar)
- Krypton (Kr)
- Xenon (Xe)
- Radon (Rn)
Electronic Configuration:
The electronic configuration of Group 18 Elements along with their symbol and atomic number is given in the tabulated form below:
Trends in the Atomic Properties:
- Atomic Radius: The nuclear radii increment on moving down the group with increasing nuclear number. This is a result of the expansion of another shell at each progressive element on moving down the group.
- Electron Gain Enthalpy: Group 18 elements exhibit very stable electronic configurations. They do not have any tendency to accept an electron.
- Ionisation Potential: They have high ionisation potentials, thanks to their closed electronic configurations. This value decreases on moving down the group due to an expansion in the nuclear size.