Which statement is true about water's density and the survival of marine life? view attachment

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.

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

What is the value of keq for the reaction expressed in scientific notation?