Answer:
[ Ga ] = 1.163 E-8 Kg/m³
Explanation:
- %wt = [(mass Ga)/(mass Si)]*100 = 5.0 E-7 %
⇒ 5.0 E-9 = m Ga/m Si
assuming: m Si = 100 g = 0.1 Kg
⇒ m Ga = (5.0 E-9)*(0.1 Kg) = 5 E-10 Kg
∴ density (δ) Si = 2.33 Kg/m³
⇒ Volume Si = (0.1 Kg)*(m³/2.33 Kg) = 0.043 m³
⇒ [ Ga ] = (5 E-10 Kg)/(0.043 m³) = 1.163 E-8 Kg/m³
⇒ [ Ga ] =
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Explanation:
Earlier, we located the valence electrons for elements Z < 20 by drawing modified Bohr structures. We can obtain these values quicker by referring to the roman numeral numbers above each family on the periodic table. The total number of valence electrons for an atom can vary between one and eight. If an element is located on the left side of the table (metal) and has less than three valence electrons, it will lose its valence in order to become stable and achieve an octet. In contrast, elements on the right side of the table (nonmetals) will gain up to eight electrons to achieve octet status.
Answer:
ΔPV = -9911 J
Explanation:
The combustion of 1 mole of heptane is:
C₇H₁₆(l) + 11O₂(g) → 7CO₂(g) + 8H₂O(l)
The change in number of moles of gas molecules is:
Δn = 7 moles products - 11 moles reactants = -<em>4 moles</em>
Using ideal gas ΔPV is:
ΔPV = ΔnRT
Where:
Δn is -4mol
R is 8,314472 J/molK
T is 298K
Replacing:
<em>ΔPV = -9911 J</em>
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I hope it helps!
Answer:
Part A. F + e⁻ → F⁻
Part B. -820 kJ
Part C. -5.45x10⁻²² kJ
Explanation:
Part A
The fluoride anion is formed when fluorine accepts an electron:
F + e⁻ → F⁻
Part B
The electron affinity is the energy necessary for the atom to accept 1 electron, which is exothermic, so it's negative. The total energy q is the electron affinity multiplied by the number of moles:
q = -328 kJ/mol * 2.5 mol
q = -820 kJ
Part C
By the Avogadros' number
1 mol --------- 6.02x10²³ atoms
x --------- 1 atom
By a simple direct three rule:
x = 1.66x10⁻²⁴ mol
So, the energy for 1 atom is:
q = -328 kJ/mol * 1.66x10⁻²⁴ mol
q = -5.45x10⁻²² kJ