When two atoms have the same number of protons but different numbers of neutrons, these atoms are different isotopes of the same element.
question 15 options:

ion

neutron

isotopes

electron

Atoms of a particular element must have the same number of protons but can have different numbers of neutrons. When an element has different variants that, while all having the same number of protons, have differing numbers of neutrons, these variants are called isotopes.

Explanation:

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of carbon is as shown here in the image.

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.