Atoms in covalent bonds do combine so as to be stable. As covalent bond consist non metals e.g O2 in this example each atom has vacance of 2 orbitals/ electrons so shairing electrons result their stability
The answer is A, good luck
PH is a measure of hydrogen(colorless, odorless) concentration of solutions. Ph is in solutions for an example like spray to clean the kitchen counter or table.These things have color and are odorless after a while.
The sun's core is where Hydrogen atoms produce energy as they convert to molecules of Helium. Helium that is produced by the conversion of hydrogen into energy is related to the solar core in the sense that the conversion process produces energy captured in the core. I hope this helps you.