Why is the chemical formula magnesium sulfide written as mgs and not mg2s2?

the answer is D

Explanation:

The chemical formula magnesium sulfide written as MgS and NOT because charge on magnesium ion is +2 and charge on sulfide ion is -2.

Therefore, these charges will cancel out each other as we write the formula in simplest crisscross  method.

Also, the numbers in a chemical formula display the total number of atoms attached with each other or central atom.

For example, in there are two chlorine atoms attached to one calcium atom.

Therefore, denotes one sulfur atom is attached to magnesium atom. Hence, we do not write the formula of magnesium sulfide as because this shows two magnesium atoms are attached to two sulfur atoms which is not true.

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.