The answer is ion, simple.
Barium has to give up 2 electrons to be like the nearest noble gas.
Planets outside solar system are referred to as exoplanets. some scientists have put forward suggestions that there could be living organisms residing in some of the exoplanets. scientists have suggested that some exoplanets are found within the habitable distance from the star they revolve around. at this distance temperature can allow existence of liquid water. Where there is water automatically there is life. so astronomers may infer that life exist in exoplanets by determining whether they are with habitable distance from their star.
<h2>Answer:</h2>
Option A is correct;
A.) The atoms are arranged differently in each molecule
<h3>Explanation:</h3>
Water and hydrogen peroxide are made of the same elements: oxygen and hydrogen. However, hydrogen peroxide (H2O2) has 1 more oxygen than water (H2O).
Hydrogen peroxide is very unstable and breaks down readily into water and a single oxygen molecule.
And also the arrangement of atoms is different in each molecule.