What happens in a double-replacement reaction? A. An element replaces an element in another compound.
B. Two reactants combine to form one compound.
C. One compound separates into two or more products.
O D. The elements in two compounds switch places

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