<u>Given:</u>
Mass of calcium nitrate (Ca(NO3)2) = 96.1 g
<u>To determine:</u>
Theoretical yield of calcium phosphate, Ca3(PO4)2
<u>Explanation:</u>
Balanced Chemical reaction-
3Ca(NO3)2 + 2Na3PO4 → 6NaNO3 + Ca3(PO4)2
Based on the reaction stoichiometry:
3 moles of Ca(NO3)2 produces 1 mole of Ca3(PO4)2
Now,
Given mass of Ca(NO3)2 = 96.1 g
Molar mass of Ca(NO3)2 = 164 g/mol
# moles of ca(NO3)2 = 96.1/164 = 0.5859 moles
Therefore, # moles of Ca3(PO4)2 produced = 0.0589 * 1/3 = 0.0196 moles
Molar mass of Ca3(PO4)2 = 310 g/mol
Mass of Ca3(PO4)2 produced = 0.0196 * 310 = 6.076 g
Ans: Theoretical yield of Ca3(PO4)2 = 6.08 g
Answer:
Explanation:
Using freezing point depression formula,
ΔTemp.f = Kf * b * i
Where,
ΔTemp.f = temp.f(pure solvent) - temp.f(solution)
b = molality
i = van't Hoff factor
Kf = cryoscopic constant
= 1.86°C/m for water
= (0 - (-5.58))/1.86
= 3.00 mol/kg
Assume 1 kg of water(solvent)
= (3.00 x 1)
= 3.00 mol.
First blank -Same
Second blank-Neutral
Answer: The partial pressure of oxygen in the mixture is 321 mm Hg
Explanation:
According to Dalton's law, the total pressure is the sum of individual pressures.

Given :
= total pressure of gases = 752 mm Hg
= partial pressure of Helium = 234 mm Hg
= partial pressure of nitrogen = 197 mm Hg
= partial pressure of oxygen = ?
Putting in the values we get:


The partial pressure of oxygen in the mixture is 321 mm Hg
<h3>1. <u>Answer;</u></h3>
a. the strong nuclear force is much greater than the electric force.
<h3><u>Explanation</u>;</h3>
- <em><u>For an atom to be stable it means it has enough amount of binding energy to hold its nucleus together permanently. </u></em>
- Therefore, <em><u>an unstable atom lacks enough amount of binding energy to hold its nucleus permanently and thus undergoes decay to achieve stability. Unstable atoms are therefore referred to being radioactive.</u></em>
-
Small atoms are stable; <u>this is because they have equal number of protons and neutrons and thus the protons and neutrons fill up energy levels while maximizing the strong force binding the nucleus together. </u>
<h3>9.<u> Answer;</u></h3>
b. change into a different element altogether.
Uranium-238 undergoes alpha decay. Therefore, uranium-238 will <em><u>change into a different element altogether</u></em>.
<h3><u>
Explanation;</u></h3>
- Unstable atoms undergo radioactive decay in order to achieve stability of their nucleus.
- <em><u>Uranium-238 is an example of such atom, which may undergo decay to achieve stability.</u></em>
- <em><u>Alpha decay is one of the types of decays,</u></em> others being beta decay and gamma decay. <em><u>In alpha decay the radioactive isotope undergoes decay such that its mass number is decreased by four and its atomic number is decreased by two.</u></em>
-
Therefore, <em><u>Uranium-238 undergoes alpha decay to form a different element whose mass number is 234 and atomic number is 90, known as thorium-234. </u></em>