An electrical device that slows the flow of charge in a circuit
2 answers:
You might be interested in
Answer:
Explanation:
One way to calculate the lattice energy is to use Hess's Law.
The lattice energy U is the energy released when the gaseous ions combine to form a solid ionic crystal:
Li⁺(g) + Cl⁻(g) ⟶ LiCl(s); U = ?
We must generate this reaction rom the equations given.
(1) Li(s) + ½Cl₂ (g) ⟶ LiCl(s); ΔHf° = -409 kJ·mol⁻¹
(2) Li(s) ⟶ Li(g); ΔHsub = 161 kJ·mol⁻¹
(3) Cl₂(g) ⟶ 2Cl(g) BE = 243 kJ·mol⁻¹
(4) Li(g) ⟶Li⁺(g) +e⁻ IE₁ = 520 kJ·mol⁻¹
(5) Cl(g) + e⁻ ⟶ Cl⁻(g) EA₁ = -349 kJ·mol⁻¹
Now, we put these equations together to get the lattice energy.
<u>E/kJ </u>
(5) Li⁺(g) +e⁻ ⟶ Li(g) 520
(6) Li(g) ⟶ Li(s) -161
(7) Li(s) + ½Cl₂(g) ⟶ LiCl(s) -409
(8) Cl(g) ⟶ ½Cl₂(g) -121.5
(9) Cl⁻(g) ⟶ Cl(g) + e⁻ <u>+349</u>
Li⁺(g) + Cl⁻(g) ⟶ LiCl(s) -862
The lattice energy of LiCl is .
Answer:
B. CA, 14
Explanation:
Atoms of elements contain small particles known as electrons, neutrons, and protons. The nucleus of an atom is made up of neutrons and protons which are at the center of the atom. Electrons on the other hand surrounds the nucleus. Electron has negative charge while proton has a positive charge. The number of neutrons is equivalent to the number of protons . In addition, the number of protons is equal to mass number minus the number of electrons.
For the compound , it can be broken down into
and
. Its ion has a mass of 34 and 18 electrons which means it has already lost 2 electrons.
Therefore:
For the given element, the number of electrons is 18+2 = 20 electrons.
The number of protons = 34 - 20 = 14.
And the number of neutrons is 14.
Only option B has the correct answer.