In the reaction, 2 A1 + 3 Br_2 rightarrow 2 AlBr_3, how many moles of aluminum w
ID: 1012058 • Letter: I
Question
In the reaction, 2 A1 + 3 Br_2 rightarrow 2 AlBr_3, how many moles of aluminum will react if 24 moles of Br_2 react and 16 moles of 2AlBr_3 are produced? 16 8 12 14 In the reaction, 2 Na(s) + 2 H_2o(l) rightarrow 2 NaOH(aq) + H_2(g), how many grams of sodium metal are consumed if 2.02g of hydrogen gas are produced? 92.0g 5.75g 11.5g 46.0g A French scientist named introduced the law of conservation of matter. .Amount of matter in a system does not change. Antoine Lavoisier Dalton Thomson Bohr Balance the following chemical reaction. ()B_4H_10 (g) + ()0_2 (g) rightarrow ()B_20_3 (g) +()H_20(g) 3, 11, 3, 5 2, 11, 4, 10 3, 12, 5, 6 6, 15, 3, 5Explanation / Answer
(1) 2Al + 3Br2 ----> 2AlBr3
According to the balanced reaction ,
2 moles of Al reacts with 3 moles of Br2
M moles of Al reacts with 24 moles of Br2
M = ( 2x24) / 3
= 16 moles of Al
So option (a) is correct
(2) 2Na + 2H2O ----> 2NaOH + H2
Molar mass of H2 is = 2x1.01 = 2.02 g/mol
Molar mass of Na = 23 g/mol
According to the balanced reaction,
2 moles = 2x23=46 g of Na produces 1 mole = 2.02 g of H2
N g of Na produces 2.02 g of H2
N = ( 2.02x46) / 2.02
= 46.0 g of Na
So option (d) is correct
(3) Antoine Lavoisier's gave the law of conservation of matter
So option (a) is correct
(4) B4H10(g) + O2(g) -----> B2O3(g) + H2O(g)
Balance B atoms : B4H10(g) + O2(g) -----> 2B2O3(g) + H2O(g)
Balance H atoms : B4H10(g) + O2(g) -----> 2B2O3(g) + 5H2O(g)
Balance O atoms : B4H10(g) + (11/2) O2(g) -----> 2B2O3(g) + 5H2O(g)
Convert the moles into integer number by multiply with 2
2B4H10(g) + 11O2(g) -----> 4B2O3(g) +10 H2O(g)
Therefore the correct option is (b)