Someone help pleas Calculate the % change in pH when 4.052 g of solid NaOH (39.997 g/mol) is added to a 394 mL buffer solution of HX 0.57 M and NaX 0.31 M?

Ka for HX is 2.0 x 10-5.

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?

What is the percent composition of ca(oh)2? 37.7% ca, 53.0% o, and 10.3% h 45.5% ca, 38.2% o, and 16.3% h 54.0% ca, 43.0% o, and 2.7% h 64.7% ca, 27.0% o, and 8.3% h

Jose and eric were given four samples in lab. the results of their analysis are shown in the table. based on the data they collected, which sample is most likely a metal?