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.
1 half-life - 4.5 days
x half-lives - 27 days
x=(1*27)/4.5=6
6 <span>half-lives have elapsed after 27 days.</span>
From the ideal gas law, PV = nRT, we can rearrange the equation to solve for T given the other parameters.
T = PV/nR
where P = 0.878 atm, V = 1.20 L, n = 0.0470 moles, and R = 0.082057 L•atm/mol•K. Plugging in our values, we obtain the temperature in Kelvin:
T = (0.878 atm)(1.20 L)/(0.0470 mol)(0.082057 L•atm/mol•K)
T = 273 K
So, the second answer choice would be correct.
Answer:
24g of NaOH are required
Explanation:
Molarity, M, is an unit of concentration widely used in chemistry defined as the ratio between moles of solute (In this case, NaOH), and volume of solution in liters.
We can find the moles of NaOH and its mass with the volume and desired concentration as follows:
<em>Moles NaOH:</em>
400.0mL = 0.400L * (1.50mol / L) = 0.600 moles NaOH
<em>Mass NaOH -Molar mass: 40.0g/mol-:</em>
0.600 moles * (40.0g / mol) =
<h3>24g of NaOH are required</h3>
Answer:
A machine have 75% efficiency means 25% of efficiency has been lost due to friction and a machine can work 75% only.
