C. 20Ne D. OF
12. A 50.0 g sample of ice well below its freezing point, at an initial temperature of -30.09
C, is slowly heated until it is a gas well above its boiling point, to a final temperature of
130° C. Data is gathered where the independent variable is the time of heating and
the dependent variable is the temperature,

Dumbledore decides to gives a surprise demonstration. he starts with a hydrate of na2co3 which has a mass of 4.31 g before heating. after he heats it he finds the mass of the anhydrous compound is found to be 3.22 g. he asks everyone in class to determine the integer x in the hydrate: na2co3·xh2o; you should do this also. round your answer to the nearest integ