Moles of MgF₂ : 1.2 x 10⁻⁴
<h3>Further explanation</h3>
Maybe the complete question is like this
<em>A student prepares 100. mL of a saturated solution of MgF2 by adding 0.50 g of solid MgF2 to 100. mL of distilled water at 25°C and stirring until no more solid dissolves. (Assume that the volume of the undissolved MgF2 is negligibly small.) The saturated solution is analyzed, and it is determined that [F−] in the solution is 2.4 × 10−3 M. </em>
<em />
The dissociation reaction of MgF₂
MgF₂(s)⇒ Mg²⁺(aq)+2F⁻(aq)
mol ratio MgF₂ : F⁻ = 1 : 2
mol of F⁻ in 100 ml solution :

mol MgF₂ :

<u>Answer: </u>The correct answer is Option B.
<u>Explanation:</u>
The given elements that is sodium and sulfur are the elements which belong to the same period that is third period.
As, the electrons are added up to the same shell across a period, the number of protons also increase and hence, they attract the electrons more effectively. This means that the effective nuclear charge also increases and the size of the sulfur thus shrink and hence, the size (atomic radius) of sodium is the largest amongst third period.
Therefore, the correct answer is Option B.
The substance you would expect to have a low melting point would be carbon dioxide, so the correct answer would be A
Answer:
Two
Explanation:
Nitrate has a charge of negative 1 and the Iron (II) tells us the iron in that formula has a charge of +2, so in order for the iron to have to equal positive two, there has to be two negative. Since on nitrate ion is -1, you need two to make -2.
(a) The heat generated in the process is 28 kJ.
(b) The work done in the process is determined as -28 kJ.
(c) The change in the internal energy is 0.
<h3>
Heat of the isothermal compression </h3>
The heat generated in the process is negative done in the process.
W = -PΔV
W = -P(V₂ - V₁)
<h3>From A to B</h3>
W = -P(VB - VA)
W = -11(7 - 12.5)
W = 60.5 L.atm = 60.5 x 101.325 J/L.atm = 6,130.16 J
<h3>From C to D</h3>
W = -25(20.5 - 7)
W = -337.5 L.atm = -34,197.18 J
Total work , w = -34,197.18 J + 6,130.16 J = -28 kJ
q = - w
q = 28 kJ
<h3>Change in internal energy</h3>
ΔE = q + w
ΔE = 28 kJ - 28 kJ = 0
Learn more about change in internal energy here: brainly.com/question/17136958
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