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Silver jewellery items tarnish slowly in air due to their reaction with ____.

Answer

Answer: \({H}_{{{2}}}{S}\)
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Reason : The primitive atmosphere was reducing in nature.
(A) If both the accertion and the reason are true and the reason is a correct explanation of the assertion
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Statement I: Alkali metals dissolve in liquid ammonia to give blue solutions.
Statement II: Alkali metals in liquid ammonia give solvated species of the type \({\left[{M}{\left({N}{H}_{{{3}}}\right)}_{{{n}}}\right]}^{{\oplus}}\) (M = alkali metals).
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\({N}_{{{2}}}{\left({g}\right)}+{3}{H}_{{{2}}}{\left({g}\right)}\rightarrow{2}{N}{H}_{{{3}}}{\left({g}\right)}\)
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(B) \({R}{a}{t}{e}=-\frac{{{d}{\left[{N}_{{{2}}}\right]}}}{{\left.{d}{t}\right.}}=-{3}\frac{{{d}{\left[{H}_{{{2}}}\right]}}}{{\left.{d}{t}\right.}}={2}\frac{{{d}{\left[{N}{H}_{{{3}}}\right]}}}{{\left.{d}{t}\right.}}\)
(C) \({R}{a}{t}{e}=-\frac{{{d}{\left[{N}_{{{2}}}\right]}}}{{\left.{d}{t}\right.}}=\frac{{1}}{{3}}\frac{{{d}{\left[{H}_{{{2}}}\right]}}}{{\left.{d}{t}\right.}}=\frac{{1}}{{2}}\frac{{{d}{\left[{N}{H}_{{{3}}}\right]}}}{{\left.{d}{t}\right.}}\)
(D) \({R}{a}{t}{e}=-\frac{{{d}{\left[{N}_{{{2}}}\right]}}}{{\left.{d}{t}\right.}}=-\frac{{{d}{\left[{H}_{{{2}}}\right]}}}{{\left.{d}{t}\right.}}=\frac{{{d}{\left[{N}{H}_{{{3}}}\right]}}}{{\left.{d}{t}\right.}}\)
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(C) \({5}{k}{m}/{h}\)
(D) \({12}{k}{m}/{h}\)
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 Reason: Velocity is a vector quantity and speed is a scalar quantity.  ( )
A. If both assertion and reason are true and the reason is the correct explanation of the assertion.  
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.  
C. If assertion is true but reason is false.  
D. If the assertion and reason both are false

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