B. The surface of a silver cup turns black when it is exposed to air.
<u>Answer:</u> The chemical formula of Iron (III) sulfate is 
<u>Explanation:</u>
Iron is the 26th element of periodic table having electronic configuration of
.
To form
ion, this element will loose 3 electrons.
Sulfate ion is a polyatomic ion having chemical formula of 
By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.
So, the chemical formula for Iron (III) sulfate is 
If the gases are at the same temperature and pressure, the ratio of their effusion rates is directly proportional to the ratio of the square roots of their molar masses:
<h3>Graham's law of diffusion </h3>
This states that the rate of diffusion of a gas is inversely proportional to the square root of the molar mass i.e
R ∝ 1/ √M
R₁/R₂ = √(M₂/M₁)
Where
- R₁ and R₂ are the rates of the two gas
- M₁ and M₂ are the molar masses of the two gas
From the Graham's law equation, we can see that the ratio of the rates of effusion of the two gases is directly proportional to the square root of their molar masses
Learn more about Graham's law of diffusion:
brainly.com/question/14004529
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The best and most correct answer among the choices provided by your question is the second choice or letter B.
<span>The most accurate measurement based on the limitations of the balance that might be found in her recorded data would be 9.2</span>
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