When a substance evaporates, what happens to the mass?
the mass increases as it changes from a liquid to a gas.
the mass decreases as it changes from a liquid to a gas.
the mass stays constant as it changes from a liquid to a gas.
there is no mass once the substance becomes a gas.

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.

How many grams of co(g) are there in 74.5 ml of the gas at 0.933 atm and 30o c?

In what environment would mineral formation caused by high pressures and high temperatures most likely occur?