Which is true about the dissolving process in water?

As a part of an experiment a student burns propane to produce carbon dioxide and water she remembers that she must follow the law conservation of matter when writing a balanced chemical equation which of these equation adheres to the law of conservation of matter

What volume of a 2.00 m stock solution of naoh is needed to prepare 150. ml of 0.40 m solution?

If two atoms are bonded to a central atom with no lone pairs,how will they be arranged