Answer:
1.930 * 10⁻⁹ mg of Mn⁺² are left unprecipitated.
Explanation:
The reaction that takes place is:
Mn⁺² + S⁻² ⇄ MnS(s)
ksp = [Mn⁺²] [S⁻²]
If the pksp of MnS is 13.500, then the ksp is:

From the problem we know that [S⁻²] = 0.0900 M
We use the ksp to calculate [Mn⁺²]:
3.1623*10⁻¹⁴= [Mn⁺²] * 0.0900 M
[Mn⁺²] = 3.514 * 10⁻¹³ M.
Now we can calculate the mass of Mn⁺², using the volume, concentration and atomic weight. Thus the mass of Mn⁺² left unprecipitated is:
3.514 * 10⁻¹³ M * 0.1 L * 54.94 g/mol = 1.930 * 10⁻¹² g = 1.930 * 10⁻⁹ mg.
The atomic number tells you the PROTONS
A. Mass of the unknown gas.
The mass of the unknown gas is calculated by subtracting the weight of the empty flask from the mass when there was air in it.
m = 126.593 g - 125.623 g
Simplifying,
m = 0.97 grams
b. Molar mass of the gas
The molar mass of the gas is calculated by the ideal gas law.
PV = (m/M)RT
where P is pressure,V is volume, m is the mass, M is the molar mass, R is the universal gas constant, and T is temperature. Substituting the known values to the equation,
(733 mmHg/760 mmHg/atm)(0.20 L) = (0.97 g/M)(0.0821 L.atm/molK)(99 + 273.15 K)
The value of M in the equation is 153.64 g/mol.
<em>Answer: 153.64 g/mol</em>
You may feel cold when you touch certain kinds of matter because some matter gives off cold air. I’m NOT SURE