Is mass conserved when 40 g of sodium hydroxide undergoes a chemical change during an interaction with 37g of hydrogen chloride? Use complete sentences to support your answer by explaining how this can be demonstrated. (10 points)

Asolution of naoh has a concentration of 25.00% by mass. what mass of naoh is present in 0.250 g of this solution? use the periodic table in the toolbar if needed. 0.0625 g what mass of naoh must be added to the solution to increase the concentration to 30.00% by mass? g