<span>Answer:
Yes, the n for potassium would be 4, and for neon would be 2.
Just count which row of the periodic table you are on.
The "L" tells you whether the highest-energy electron is in
an "s" orbital (L=0) or a "p" orbital (L=1) or a "d" orbital (L=2) or an "f" orbital (L=3).
The manner in which these orbitals are filled is:
for each of the first three rows (up to argon),
two electrons in the "s" orbital are filled first, then 6 electrons in the "p"orbitals.
The potassium row also starts with filling the "s" orbital at the new "n" level (4)
but then goes back to filling up the "d" orbitals of n=3 before it fills up the "p"s for n=4.
OK, so potassium has n=4, L = 0, while neon has n=2, L = 1.
The quantum numbers connected with "an element" are always referring to the
highest-energy electron, i.e., the one that was absent in the predecessor element
of the periodic table. When you go from potassium to calcium,
you still get n=4, L = 0, because there are two positions in the "s" orbital.
But when you go from calcium to scandium, suddenly you go back to n=3, L = 2 ("d" orbital).</span>
<span>google it and you should have the answer I had the same problem </span>
Hello!
The pKa of an indicator tells us the pH where it changes color. The pKa of Methyl red is

So, at a pH=7,8,
Methyl Red would be at a pH over its pKa, so it would be in its basic form. The Basic Form of Methyl Red is Yellow, so
the solution would be Yellow.Have a nice day!
Answer:
a. Interference patterns are observed when a wave passes through a barrier with two slits
Explanation:
Interference is a situation where two waves superimpose to form a new wave of a different amplitude. This amplitude can be greater, same or lower.
the diagram attached below shows the movement of a wave through a barrier with two slits.
you can notice the portions of the wave that overlap. This overlapping of waves is the interference.
Thus, option A is correct.
The other options however, are not correct. as shown below:
Option B is wrong as waves exhibit diffraction <em>(it is diffraction of the light wave that produces the rainbows we see in the sky)</em>
Option C is wrong as waves do not travel straight through slits always.
Option D is wrong as waves can also interfere constructively and destructively.
Chemical reaction: C₃H₇COOH → C₃H₇COO⁻ + H⁺.
c(<span>butanoic acid) = 0,100 M.
</span>α = 1,23% = 0,0123.
Ka = α² · c / 1 - α.
Ka = 0,0123² · 0,1 M / 1 - 0,0123.
Ka = 0,0000153 M.
Ka = c(C₃H₇COO⁻) · c(H⁺) / c(C₃H₇COOH).
c(H⁺) = α · c(C₃H₇COOH).
c(H⁺) = 0,0123 · 0,1 M = 0,00123 mol/L.
pH = -log c(H⁺).
pH = 2,91.