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Mass of X₄Z₅= 378.621 g
<h3>Further explanation</h3>
Given
3.89 x 10²³ molecules/formula units of X₄Z₅
Required
Mass of X₄Z₅
Solution
1 mol = 6.022 x 10²³ particles(molecules, atoms, ions)
N = n x No
No = Avogadro's number
n = mol
Conversion to mol :
n = N : No
n = 3.89 x 10²³ : 6.022 x 10²³
n = 0.646
MW X₄Z₅ :
= 4 x 76.15 + 5 x 56.3
= 304.6 + 281.5
= 586.1 g/mol
Mass :
= mol x MW
= 0.646 x 586.1
= 378.621 g
Answer:
None of them
Explanation:
The number of moles in 75ml is 0.01875moles while in 25ml is 0.004375 and in 129 ml is 0.018705.
REMEMBER: Molarity is the number of moles per litre so in order to get the number of moles you multiply the molarity of the substance by the quantity of the substance in litres.
The radius of the anion is 7.413 nm
<h3>How to calculate the force of attraction between charges</h3>
The force of attraction (F) is given by the formula:
- F = (1/4π∈r²)(Zc*e)(Za*e)
where:
∈ = permittivity of free space = 8.85*10⁻¹⁵ F/m
Zc = charge on the cation = +2
Zc = charge on the anion = -2
e = charge on an electron = 1.602 * 10⁻¹⁹ C
r = interionic distance
r = rc + ra
where rc and ra are the radius of the cation and anion respectively
F = 1.64 * 10⁻⁸ N
Therefore based on the equation of force of attraction:
1.64 *10⁻⁸ = [1/4π(8.85*10⁻¹⁵)r²](2 * 1.602*10⁻¹⁹)²
r² = 5.63 * 10⁻¹⁷
r = 7.50 nm
Since r = rc + ra
where rc = 0.087 nm
thus, ra = r - rc = 7.50 - 0.087
ra = 7.413 nm
Therefore, the radius of the anion is 7.413 nm
Learn more about ionic radius at: brainly.com/question/2279609