The electron in a hydrogen atom with an energy of -0.544 eV is in a subshell with 18 states.

What is the principal quantum number, n, for this atom?

What is the maximum possible orbital angular momentum this atom can have?

Is the number of states in the subshell with the next lowest value of l equal to 16, 14, or 12?

Bassed upon the energy level, n^2 = 13.6/.544 = 25, and n = 5. That n state has 2 n^2 = 50 substates.

The maximum orbital angular momentum quantum number for this n-value is
(lower case L) = n-1 = 4. The orbital angular momentum of that state is 4 h, where h is Planck's constant.

For the next lower orbital quantum number of that n-state, L = 3, there are
2*(2L + 1) = 14 subshells.
The L projections are -3, -2, -1, 0, 1, 2 and 3, with two electron spin projections per L projection.

To find the principal quantum number (n) for the given energy of the electron in a hydrogen atom, we can use the equation:

E = -(13.6 eV) / (n^2)

Where E is the energy of the electron and n is the principal quantum number.

Rearranging this equation to solve for n, we have:

n^2 = -(13.6 eV) / E

n^2 = -(13.6 eV) / (-0.544 eV)

n^2 = 25

Taking the square root of both sides, we find:

n = 5

So, the principal quantum number (n) for this hydrogen atom is 5.

Next, to find the maximum possible orbital angular momentum for this atom, we can use the equation:

L = sqrt(l(l + 1)) * h / (2π)

Where L is the orbital angular momentum, h is Planck's constant, and l is the azimuthal quantum number.

Since the hydrogen atom has only one electron, l can be any integer value from 0 to (n-1). In this case, with n = 5, the possible values for l are 0, 1, 2, 3, and 4.

By calculating L for each value of l and selecting the maximum value, we can determine the maximum possible orbital angular momentum.

L(0) = sqrt(0(0 + 1)) * h / (2π) = 0
L(1) = sqrt(1(1 + 1)) * h / (2π) = sqrt(2) * h / (2π)
L(2) = sqrt(2(2 + 1)) * h / (2π) = sqrt(6) * h / (2π)
L(3) = sqrt(3(3 + 1)) * h / (2π) = sqrt(12) * h / (2π)
L(4) = sqrt(4(4 + 1)) * h / (2π) = 2 * h / π

Comparing these values, we see that L(4) is the largest. Therefore, the maximum possible orbital angular momentum for this atom is 2 * h / π.

Finally, to determine the number of states in the subshell with the next lowest value of l, we need to understand the relationship between l and the number of states in a subshell.

The number of states in a subshell is given by the formula:

Number of states = 2 * l + 1

For the current subshell with 18 states, we can write the equation:

18 = 2 * l + 1

Subtracting 1 from both sides, we find:

17 = 2 * l

Dividing both sides by 2, we get:

l = 8.5

Since l must be an integer value, the closest integer value to 8.5 is 9. Therefore, the number of states in the subshell with the next lowest value of l is:

Number of states = 2 * 9 + 1 = 19

So, the number of states in the subshell with the next lowest value of l is 19, which is not among the provided options of 16, 14, or 12.