A +2 ~B AB _ 2 36.0 g of 'A' (Molar mass: 60 ~g ~mol ^ -1 ) and 56.0 g of ' B ^ (Molar mass: 80 ~g ~mol ^ -1 ) are allowed to react. Which of the following statements are correct ? A. 'A' is the limiting reagent. B. 77.0 ~g of AB _ 2 is formed. C. Molar mass of A B_ 2 is 140 ~g ~mol ^ -1 . D. 15.0 ~g of A is left unreacted after the completion of reaction. Choose the correct answer from the options given below :
D. B and D Only
Reaction: A + 2B → AB₂. Moles of A = 36.0/60 = 0.6 mol; Moles of B = 56.0/80 = 0.7 mol. A requires 1.2 mol of B but only 0.7 available, so B is limiting reagent. So, (A) False - B is limiting. (B) AB₂ formed = 0.7/2 = 0.35 mol; Molar mass AB₂ = 60 + 2(80) = 220 g/mol; Mass = 0.35 × 220 = 77 g True. (C) False - Molar mass is 220 g/mol. (D) A remaining = 0.6 - 0.35 = 0.25 mol = 15 g True. Correct statements: B and D.
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