Density is mass divided by volume.
49g/14cm^3 = 3.5 g/cm^3
The answer is D glad to help :)<span />
Answer:
B. 4 Fe + 3 0₂---> 2 Fe₂O3
Explanation:
(A) Ir + O₂--> IrO₂ No: Ir is iridium
(B) 4 Fe + 3 0₂---> 2 Fe₂O3 Yes: Fe is iron and O is oxygen, and the equation is balanced.
(C) I+ 0₂ ---> 10₂ No: I is iodine
(D) 3 Ir + 0₂ -> 6 Ir₂03 No: I is iodine
I believe there are 3 significant figures B.