Answer: 1. 3.914 × ^10-4 | 2. 4.781 × ^10-1
Explanation:
Answer:
92.49 %
Explanation:
We first calculate the number of moles n of AgBr in 0.7127 g
n = m/M where M = molar mass of AgBr = 187.77 g/mol and m = mass of AgBr formed = 0.7127 g
n = m/M = 0.7127g/187.77 g/mol = 0.0038 mol
Since 1 mol of Bromide ion Br⁻ forms 1 mol AgBr, number of moles of Br⁻ formed = 0.0038 mol and
From n = m/M
m = nM . Where m = mass of Bromide ion precipitate and M = Molar mass of Bromine = 79.904 g/mol
m = 0.0038 mol × 79.904 g/mol = 0.3036 g
% Br in compound = m₁/m₂ × 100%
m₁ = mass of Br in compound = m = 0.3036 g (Since the same amount of Br in the compound is the same amount in the precipitate.)
m₂ = mass of compound = 0.3283 g
% Br in compound = m₁/m₂ × 100% = 0.3036/0.3283 × 100% = 0.9249 × 100% = 92.49 %
Answer:
Spontaneous and random. Decay is called spontaneous because the occur on their own and are unaffected by external factors like temperature, pressure, and many more. Decay is called random because we cannot determine the rate at which it decays but can only determine the probability of the decay.Oct 21, 2015
Explanation:
Answer : The correct option is, (D) 
Explanation :
(A) 
This reaction is a double displacement reaction in which the cation and anion of two reactants are exchange their places to give two different products.
(B) 
This reaction is a decomposition reaction in which the larger molecule decomposes to give two or more products.
(C) 
This reaction is a neutralization reaction in which an acid and a base react to give a salt and water as a product.
(D) 
This reaction is a redox reaction in which the oxidation and reduction reaction occur simultaneously.
Oxidation reaction is the reaction in which a substance looses its electrons. In this oxidation state increases.
Reduction reaction is the reaction in which a substance gains electrons. In this oxidation state decreases.
In this reaction, magnesium shows oxidation due to change in oxidation number from (0) to (+2) and hydrogen shows reduction due to change in oxidation number from (-1) to (0).
Hence, the correct option is, (D)