Question

What is the mass percentage of O in CaO ? *
1 point
32.8
40
16
28.5

Answer 1

Answer:

the mass percentage of o in cao is 28.531%

Answer 2

Answer :

➤ For determining the % composition of each element in a compound :

$\boxed{\bf{Mass\:\%=\dfrac{mass\:of\:that\:element\:in\:the\:compound\times 100}{molar\:mass\:of\:the\:compound} }}$

Atomic weight of Ca = 40

Atomic weight of O = 16

Molar mass of CaO = 40+16 = 56

➙ %O = 16×100/56

➙ %O = 1600/56

➙ %O = 28.57%

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