Answer : The change in entropy is 
Explanation :
Formula used :
where,
= change in entropy = ?
m = mass of water = 1.00 kg
= heat of vaporization of water = 
T = temperature = 
Now put all the given values in the above formula, we get:
Therefore, the change in entropy is
Answer:
These tests determine the solubility of the compounds formed upon adding the test solution
Explanation:
Addition of Ba(NO₃)₂ will cause a precipitate ((Ba)₂SO₄) to form in the solution of (NH₄)₂SO₄. No precipitates will form in the other unknown solutions. Thus, whether or not the solution is ammonium sulfate can be determined.
Addition of NaCl solution will cause a precipitate (AgCl) to form in the solution of AgNO₃. No precipitates will form in the other unknown solutions. Thus, whether or not the solution is silver nitrate can be determined.
If no precipitates form, then the unknown solution must be KCl.
Answer:
B) we will convert the 10 g of NaCl into moles.
Explanation:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
we will convert the 10 g of NaCl into moles.
Number of moles of NaCl:
Number of moles = mass/molar mass
Number of moles = 10 g/ 58.44 gmol
Number of moles = 0.17 mol
1 Kg = 1 L
Molarity = 0.17 mol / 2 L
Molarity = 0.085 mol/L
Molarity = 0.085 M
If a sample of white gold alloy contains 60 percent by mass of gold while the remaining is platinum, then the alloy would contain 40 percent by mass of platinum. <span>Percentage
by mass is the amount in mass units of a component in a mixture per 100 unit if mass of the
total mixture. We are given the amount of gold available, this represents the 60 percent of the alloy. We calculate for the amount of platinum needed as follows:
Percent of platinum = mass of platinum / mass of gold + mass of platinum
0.40 = mass of platinum / 175 g + mass of platinum
mass of platinum = 117 g</span>
