<span>B) The crystals did not phosphoresce within the drawer but did expose the film</span>
Answer:
Explanation:
Cu²⁺ + 2e⁻ → Cu ( copper gets reduced )
Cu → Cu²⁺ + 2e⁻ ( copper gets oxidized )
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Consider the following reactions.
4KI + 2CuCl₂ → 2CuI + I₂ + 4KCl
the oxidation state of copper is changed from +2 to +1 so copper get reduced.
CO + H₂O → CO₂ + H₂
the oxidation state of carbon is +2 on reactant side and on product side it becomes +4 so carbon get oxidized.
Na₂CO₃ + H₃PO₄ → Na₂HPO₄ + CO₂ + H₂O
The oxidation state of carbon on reactant side is +4. while on product side is also +4 so it neither oxidized nor reduced.
H₂S + 2NaOH → Na₂S + 2H₂O
The oxidation sate of sulfur is -2 on reactant side and in product side it is also -2 so it neither oxidized nor reduced.
Answer:
The answer to your question is given below.
Explanation:
To prepare 50mL of 3M HCl, we must calculate the volume of the stock solution needed. This can obtained as follow:
Molarity of stock solution (M1) = 12M
Volume of stock solution needed (V1) =?
Molarity of diluted solution (M2) = 3M
Volume of diluted solution (V2) = 50mL
The volume of the stock solution needed can be obtained by using the dilution formula as shown below:
M1V1 = M2V2
12 x V1 = 3 x 50
Divide both side by 12
V1 = (3 x 50)/12
V1 = 12.5mL
The volume of the stock solution needed is 12.5mL
Therefore, to prepare 50mL of 3M HCl, we must measure 12.5mL of the stock solution i.e 12M HCl and then, add water to the mark in a 1L volumetric flask. Now we can measure out 50mL of the solution.
Complete Question
The complete question is shown on the first uploaded image
Answer:
The concentration of high-pressure side is 
Explanation:
From the question we are told that
The thickness of the polyethylene is 
The temperature is 
The flux is 
The concentration on the low-pressure side is 
The initial diffusivity is 
The activation energy for diffusion is 
Generally the diffusivity of the oxygen at 600 K can be mathematically evaluated as
substituting values
Generally the flux is mathematically represented as
Where 
is the concentration of oxygen at the higher side
So
substituting values
What are <span>stoichiometry equations?</span>
