A researcher adds 3.25 L of water to a 6.75 L solution of sodium hydroxide. If the final solution has a concentration of 1.25 M after dilution, what was the initial concentration of the solution?

Aballoon inflated with three breaths of air has a volume of 1.7 l. at the same temperature and pressure, what is the volume of the balloon if five more same-sized breaths are added to the balloon? a balloon inflated with three breaths of air has a volume of 1.7 l. at the same temperature and pressure, what is the volume of the balloon if five more same-sized breaths are added to the balloon?

Iknow #2 is d. i just need to know why

If the density of water is 1.0 g/cm3, which of these materials would float in water, based on their densities? check all that apply. aluminum cork iron lead wax