The atoms of which of the following pair of elements are most likely to exist in free state ?(a) hydrogen and helium (b) argon and carbon (c) neon and nitrogen (d) helium and neon

Academic Chemistry NCERT Class 9

Correct Answer: (d) helium and neon

Explanation: Atoms of helium and neon exist in a free state because they are inert gases and chemically inactive.

Tutorialspoint

Simply Easy Learning

Updated on: 10-Oct-2022

35 Views

Why do Helium, Neon and Argon have a zero valency?
What are Hydrogen and Helium?
Which of the following gases can be used for storage of fresh sample of an oil for a long time?(a) Carbon dioxide or oxygen(b) Nitrogen or oxygen(c) Carbon dioxide or helium(d) Helium or nitrogen
Give the formulae of the compounds formed from the following sets of elements :(a) calcium and fluorine(b) hydrogen and sulphur(c) nitrogen and hydrogen(d) carbon and chlorine(e) sodium and oxygen(f) carbon and oxygen
If Jupiter and Saturn consist mainly of hydrogen and helium then why they are cold? As the sun is also made of hydrogen and helium and it is really hot.
Which of the following elements has the same molecular mass as its atomic mass ?(a) nitrogen (b) neon (c) oxygen (d) chlorine
(a) Lithium, sodium, potassium are all metals that react with water to liberate hydrogen gas. Is there any similarity in the atoms of these elements?(b) Helium is an unreactive gas and neon is a gas of extremely low reactivity. What, if anything, do their atoms have in common?
The correct increasing order of the boiling points of liquid oxygen, liquid argon and liquid nitrogen present in liquid air is :(a) nitrogen, oxygen, argon (b) nitrogen, argon, oxygen(c) argon, oxygen, nitrogen (d) oxygen, argon, nitrogen
Which of the following symbols of elements are incorrect? Give their correct symbols(a) Cobalt CO(b) Carbon c(c) Aluminium AL(d) Helium He(e) Sodium So
State the number of electrons present in the outermost shell of the atoms of the following elements :(i) Neon (ii) Chlorine
One of the following elements has an atomicity of 'one'. This element is :(a) helium (b) hydrogen (c) sulphur (d) ozone
Two elements X and Y have valencies of 5 and 3, and 3 and 2, respectively. The elements X and Y are most likely to be respectively :(a) copper and sulphur (b) sulphur and iron(c) phosphorus and nitrogen (d) nitrogen and iron
Which of the following cannot be separated from air by the process of fractional distillation ?(a) oxygen (b) argon (c) hydrogen (d) nitrogen
(a) Why does the size of the atoms progressively become smaller when we move from sodium (Na) to chlorine (Cl) in the third period of the periodic table?(b) Helium and neon are unreactive gases. What, if anything, do their atoms have in common?
The elements which normally exist in the liquid state are :(a) bromine and iodine (b) mercury and chlorine(c) iodine and mercury (d) bromine and mercury

Kickstart Your Career

Get certified by completing the course

Get Started

Advertisements