A 43.9 ml sample of a 0.394 M aqueous hydrocyanic acid solution is titrated with a 0.357 M aqueous barium hydroxide solution. What is the pH after 9.06 mL of base have been added? pH =

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

Compare and contrast physical changes with chemical changes.

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons