Mass percent is one way of expressing concentration of a solution. It is expressed as the mass of solute per mass of solution. For this case, mass percent is calculated as follows:
% mass = 140 g NaCl / (140 g NaCl + 4500 mL ( 0.997 g/mL)) x 100
% mass = 3.03 %
For lead fluoride Ksp = s³
For Aluminum hydroxide Ksp = s⁴
<u>Explanation:</u>
The expression for the solubility product can be written as the product of the concentration of the ions present in the solution.
PbF₂ → Pb²⁺ + 2 F⁻
Then the Ksp can be written as,
Ksp = [ Pb²⁺] [F⁻]²
If the concentration can be considered as s, then the Ksp can be written as,
Ksp = s× s² = s³
For Aluminum hydroxide on dissociation it gives 4 ions as,
Al(OH)₃ → Al³⁺ + 3 OH⁻
Ksp = [Al³⁺] [OH⁻]³
= s × s³ = s⁴
Thus,For lead fluoride Ksp = s³
For Aluminum hydroxide Ksp = s⁴
Alpha particles are released by high mass, proton rich unstable nuclei. The alpha particle is a helium nucleus; it consists of two protons and two neutrons. It contains no electrons to balance the two positively charged protons. Alpha particles are therefore positively charged particles moving at high speeds.
Answer:
5.31x10⁻⁶ C
Explanation:
The cube is located 100 m altitude from the ground, so the superior face is at 100m and has E = 70 N/C, and the inferior face is at the ground with E = 130 N/C.
The electric field is perpendicular to the bottom and the top of the cube, so the total flux is the flux at the superior face plus the flux at the inferior face:
Фtotal = Ф100m + Фground
Where Ф = E*A*cos(α). α is the angle between the area vector and the field (180° at the topo and 0° at the bottom):
Фtotal = E100*A*cos(180°) + Eground*A*cos(0°)
Фtotal = 70A*(-1) + 130*A*1
Фtotal = 60A
By Gauss' Law, the flux is:
Фtotal = q/ε, where q is the charge, and ε is the permittivity constant in vacuum = 8.854x10⁻¹² C²/N.m²
A = 100mx100m = 10000 m²
q = 60*10000*8.854x10⁻¹²
q = 5.31x10⁻⁶ C
