Hydrogen Test 7

Permanent hardness of water can be removed by using washing soda. Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates.

For a chemical element the number of protons found in its nucleus is known as its atomic number. Atomic number is unique for each and every element so it is considered as the basis of the periodic table formation. Earlier mass numbers were considered but due to some irregularities it was dismissed.

The nucleus of an atom consists of neutrons and protons. And the whole mass of the atom is decided on the basis of the mass of the nucleus because the mass of electrons present outside the nucleus is very negligible as compared to mass of protons and neutrons.

So the formula to calculate mass number is as follows:

Mass number = Number of protons + Number of neutrons

And for a hydrogen atom which is represented as the atomic number is one and the mass number is also one therefore both are equal. And we know that the number of protons is equal to the atomic number, therefore the number of protons is also one.

By putting the values in the above formula we get:

Number of neutrons = 1 - 1 = 0

Hence the number of neutrons present in the hydrogen atom is also zero.

So from the above discussions we can say that Assertion i.e. the mass number of hydrogen is equal to the atomic number is correct. And the Reason i.e. hydrogen atoms have no neutrons is also correct and reason is the correct explanation for assertion.

Some metals like platinum and palladium can be used as storage media for hydrogen as they will not react with the atomic hydrogen due to their inertness. They absorb large volumes of hydrogen as they have high surface area which allows hydrogen to get adsorbed over their surface.

Correct assertion: D₂O is called heavy water.

Correct reason: Due to stronger D-O bonds, the degree of dissociation of D₂O is lower than that of H₂O.

H₂O₂ is more extensively associated by hydrogen bonding than water.

The electronegativity difference between Be (1.5) and H (2.1) is small.

O₂F₂ has the similar structure as that of H₂O₂ but the O - O bond length is shorter in O₂F₂ than in H₂O₂. This is due to the high electronegativity of attached F-atoms. H₂O₂ is a covalent compound.