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2. A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrate concentration in the resulting solution?
A. 21.8 M
B. 0.459 M
C. 2.18 ´ 10-2 M
D. 8.72 ´ 10-2 M
E. 0.109 M
10. What is the theoretical yield of chromium that can be produced by the reaction of 40.0 g of Cr2O3 with 8.00 g of aluminum according to the chemical equation below?
2Al + Cr2O3 ® Al2O3 + 2Cr
A. 7.7 g
B. 15.4 g
C. 27.3 g
D. 30.8 g
E. 49.9 g