I think the answer is 1s²2s²2p⁶. Since neon has an atomic number of 10, we know that it needs to have 10 electrons and since it is in the second row it cannot have any d electrons which makes the first option incorrect. The second option is incorrect because the 2s⁴ can't exist since s orbitals can only hold 2 electrons. The fourth option cannot be right because it again neon cannot have d electrons due to it being in the second row.
I hope this helps. Let me know if anything is unclear.
Answer:
M₂ = 1.9 M
Explanation:
Given data;
Volume of sodium chloride = 200 mL
Molarity of sodium chloride = 4.98 M
Volume of water = 532 mL
Final Molarity = ?
Solution:
M₁V₁ = M₂V₂
M₂ = M₁V₁ /V₂
M₂ = 4.98 M × 200 mL / 532 mL
M₂ = 996 mL. M /532 mL
M₂ = 1.9 M
Answer: 12.0 milliliters of 6.50 M HCl ( aq ) are required to react with 2.55 g Zn.
Explanation:
moles =
moles of zinc =
The balanced chemical equation is :

According to stoichiometry:
1 mole of zinc reacts with = 2 moles of HCl
Thus 0.0390 moles of zinc reacts with =
moles of HCl
To calculate the volume for given molarity, we use the equation:
.....(1)
Molarity of
solution = 6.50 M
Volume of solution = ?
Putting values in equation 1, we get:


Thus 12.0 ml of 6.50 M HCl ( aq ) are required to react with 2.55 g Zn
Molarity = mol/L
0.175 mol
0.15 L (1000 mL = 1 L)
Molarity = 0.175 mol/0.15 L = 1.1666667 M