Look at picture and answer will mark brainliest. Please explain your answer

Which of the following is a compound? a.carbon b.oxygen c.hydrogen d.water

Bose-einstein condensation occurs at what temperature?

The covalent compound acetylene, which is the fuel of the oxyacetylene torch used by welders, has the molecular formula c2h2. the covalent compound benzene, a commercial solvent, has the molecular formula c6h6 each of these covalent compounds contains carbon and hydrogen atoms in a one-to-one ratio. would it be correct to write the chemical formulas of each as ch? explain.