The fictitious element concordium (Cn) has two naturally occurring isotopes: 65C (64.8913 u) and 69C (68.9385 u). The atomic mass of concordium is 66.91 u. What is the percentage abundance of 65Cn? Select one: O A. 50.12 % B. 34.11 % C. 41.37 % D. 65.89 % O E. 49.88 %

When 0.210 g of iron (atomic weight = 55.85 g/mol) is burned, 0.341 g of iron oxide is obtained. What is the mass percent of iron in the iron oxide? Given that the atomic weight of Oxygen = 16.00 g/mol. %3D a. 75.5% O b. 73.3% c. 61.6% d. 83.1% e. 77.9%

In 5. How many nitrogen atoms are there in a 346 g sample of pure ammonia (NH3, 17.031 g/mol)? b) 2.0 x 1025(3k0 c) 5.00 x 1022 5.88 00ubong of bebeen sh6 (lom\g 22.00) JEToiro mulzestoq lo amsig ymom wol a) 3.68 x 1025 d) 2.15 x 1025 00.5 to 190mst s te ZAS (d ESA (b T.OI (6

It was found that 3.85 g of a compound of phosphorus and chlorine contained 0.165 g of phosphorus. What are the percentages by mass of phosphorus and chlorine in this compound? O 10.5% P and 89.5% CI 4.29% P and 95.7% CI 35.0% P and 65.0% CI O 20.6% P and 79.4% CI