(A)Atoms are not able to exist independently.

Atoms can accept or donate electrons to form a stable electronic configuration.

It results in the formation of the molecule.

Only inert gases, on the other hand, already have octet-filled configurations, allowing them to exist as atoms. Hence, option (A) is correct

Additional Information:

(B)Atoms are the basic units from which molecules and ions are formed.

Two or more two atoms are combined and form a molecule.

These atoms can be the same or different and based on that the molecules can be homonuclear or heteronuclear molecules.

When an atom accepts or donates electrons it forms ions.

(C)Atoms are always neutral in nature.

An atom has an equal number of protons and electrons.

So atoms are always neutral in nature.

(D)Atoms aggregate in large numbers to form the matter that we can see, feel or touch.

Atoms are very small in size, so can not be seen by naked eyes.

When atoms are aggregated in large numbers to form matter then we can see, feel or touch.

Number of moles (n)=w / M

Where,

W is the given weight of the compound in grams

M is the molar mass of the compound

Number of moles in 1g H2

=1 / 2

= 0.5 mol

Therefore, it has the maximum number of molecules.

Step 2: Calculation of the number of molecules

Number of molecules in 1g H₂ = n × NA

Where,

NA is Avogadro's number which is equal to 6.022 × 10²³

Number of molecules in 1g H₂

= 0.5 × 6.022 × 10²³

= 3.011 × 10²³ molecules. Hence the correct option is B

1. It is given that element X is divalent. A divalent ion implies the element has a charge of 2 units. The valency of X is 2 units.

2. The element Y is tetravalent. A tetravalent ion implies the element has a charge of 4 units. The valency of Y is 4 units.

3. According to the concepts of bond formation, If the valency of an element is x and the valency of another element is y. The compound formed by the two elements is.

4. Using the property mentioned above, the valency of one element is 2 and the valency of the other element is 4. Hence the correct option is A.

Additional Information: Valency is the number of atoms of a particular element that are combined with one atom of another element to form a molecule. Valency is also known as molecular weight. Valency is a measure of the combined power of an atom. The valency of an element is determined by the number of electrons in its outermost shell.

So there is only a nitrate ion for each potassium ion. Hence the correct option is A.