An element has the following natural abundances and isotopic masses: 90.47% abundance with 19.98 amu, 0.28% abundance with 20.98 amu, and 9.26% abundance with 22.00 amu. Calculate the average atomic mass of this element. (Enter an unrounded value.)

Rutherford's experiment indicated that matter was not as uniform as it appears what part of his experimental results implied this idea

Calculate the change in entropy if br2(l) is converted into gaseous br atoms. s° for br2(l) = 152.2 j/(mol•k) s° for br2(g) = 245.5 j/(mol•k) s° for br(g) = 175.0 j/(mol•k)

Harvey kept a balloon with a volume of 348 milliliters at 25.0˚c inside a freezer for a night.  when he took it out, its new volume was 322 milliliters, but its pressure was the same.  if the final temperature of the balloon is the same as the freezer’s, what is the temperature of the freezer? the temperature of the freezer is  kelvins.