Unknown element X combines with oxygen to form the compound XO2. If 44.0 grams of element X combines with 8.00 grams of oxygen, what is the atomic mass of element X?
A. 16 amu
B. 44 amu
C. 88 amu
D. 176 amu
E. 352 amu



Answer :

Oxygen has a Mr of 16 and half of 16 is 8 which is how many grams used. If 44 grams of X is used it must have an amu of 88. (Times 2)