To create the Lewis structure we need to take into account the octet rule: atoms tend to gain, lose or share electrons to complete their valence shell with 8 electrons.
C belongs to Group 4A in the periodic table so it has 4 valence electrons. It needs to share 4 pairs of electrons to complete the octet.
F belongs to Group 7A in the periodic table so it has 7 valence electrons. Each F needs to share 1 pair of electrons to complete the octet.
As a consequence, in CF₄, C will form a single bond with each F and all the octets will be complete.
<h3>Answer:</h3>
2.55 × 10²² Na Atoms
<h3>Solution:</h3>
Data Given:
M.Mass of Na = 23 g.mol⁻¹
Mass of Na = 973 mg = 0.973 g
# of Na Atoms = ??
Step 1: Calculate Moles of Na as:
Moles = Mass ÷ M.Mass
Moles = 0.973 g ÷ 23 g.mol⁻¹
Moles = 0.0423 mol
Step 2: Calculate No, of Na Atoms as:
As 1 mole of sodium atoms counts 6.022 × 10²³ and equals exactly to the mass of 23 g. So, we can write,
Moles = No. of Na Atoms ÷ 6.022 × 10²³ Na Atoms.mol⁻¹
Solving for No. of Na Atoms,
No. of Na Atoms = Moles × 6.022 × 10²³ Na Atoms.mol⁻¹
No. of Na Atoms = 0.0423 mol × 6.022 × 10²³ Na Atoms.mol⁻¹
No. of Na Atoms = 2.55 × 10²² Na Atoms
<h3>Conclusion: </h3>
2.55 × 10²² sodium atoms are required to reach a total mass of 973 mg in a substance of pure sodium.
The unknown medium would be glass
Answer:
there will be 8 electrons
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!
