The answer is the option<span> 3.) Fixing a wineglass requires a large decrease in entropy.
Entropy is a termodynamical variable and it is defined as the degree of disorder of the system.
As per the second law of thermodynamics the spontaneous changes only occur when the entropy increases.
</span>Fixing the broken glasses by itself meant to decrease the entropy spontaneusly which violate the principle or second law of thermodynamics. So, it is not possible.
This can be done through electrolysis. Electrolysis is the separation of a substance into two or more substances that may differ from each other and from the original substance by passing an electric current through a solution that contains ions.
In the case of copper, we use a copper (II) sulphate solution which we put in a large beaker. The impure copper will be used as the positive electrode (anode) and for the negative electrode (cathode) will be a bar of pure copper.
When the electric current is switched on, the bar of pure copper which is the cathode increases greatly in size as copper ions leave the anode of impure copper and attach to the cathode. The anode becomes smaller and smaller as it loses copper ions until all that is left of it is impurities in form of a sludge beneath it.
Answer:
Explanation:
They gave us the masses of two reactants and asked us to determine the mass of the product.
This looks like a limiting reactant problem.
1. Assemble the information
We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.
Mᵣ: 239.27 32.00 207.2
2PbS + 3O₂ ⟶ 2Pb + 2SO₃
m/g: 2.54 1.88
2. Calculate the moles of each reactant
3. Calculate the moles of Pb from each reactant
4. Calculate the mass of Pb
For an aqueous solution to conduct electricity, ions must be
present in solution.
This means soluble salts will conduct electricity. Also,
since acids and bases have ions in solution, they could also conduct electricity.
Option 1 is a soluble salt. Options 2 and 4 are base and acid respectively.
Option 3, though soluble in water, exist as a molecule, therefore its solution
cannot conduct electricity.
