Answer: 0.0257 moles of
and 0.0257 moles of 
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

moles of 
The balanced reaction for dissociation will be:
According to stoichiometry:
1 mole of
gives 1 mole of
and 1 mole of 
Thus there will be 0.0257 moles of
and 0.0257 moles of 
We are given –
- Mass of
is 57.1 g and we are asked to find number of moles present in 57.1 g of 






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Now,Let's calculate the number of moles present in 57.1 g of 






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Answer:
B. Ca2+ import into the ER because it has the steeper concentration gradient
Explanation:
ΔGt = RT㏑(C₂/C₁)
where ΔGt is the free energy change for transport; R = 8.315 J/mol; T = 298 K; C₂/C₁ is ratio of concentrations inside and outside each organelle.
For Ca²⁺ import
ΔGt = 8.315 J/mol * 298 K * ㏑(10⁻³/10⁻⁷)
ΔGt= 3.42 kJ/mol
For H⁺ import
ΔGt = 8.315 J/mol * 298 K * ㏑ (10⁻⁴/10⁻⁷)
ΔGt = 2.73 kJ/mol
From the above values, ΔGt is greater for Ca²⁺ import because it has a steeper concentration gradient
We have as a reagent a salt, lead nitrate (Pb(NO3)2), and an unknown solution that gives us as a product lead chloride (PbCl2). That is, the solution must contain chlorine.
If a chlorine solution is used we will have the following reaction:

So, with a chlorine solution, we will have a white precipitate of lead chloride.