Answer:
I think temperature. sorry if the answer is wrong
I think it is B) 18 but you'd have to check. Help?
The bond that exist between two oxygen atoms is
called a double covalent bond. This bond involves the sharing of four electrons
to obtain a more stable structure. This type of bond is much stronger than the
single covalent bond. They are much harder to break.
Expression for the Balmer series to find the wavelength of the spectral line is as follows:
1 / λ = R

Where, λ is wavelength, R is Rydberg constant, and n is integral value (4 here → Fourth level)
Substitute 1.097 x 10⁷ m⁻¹ for R and 4 for n in the above equation
1 / λ = (1.097 x 10⁷ m⁻¹)
= 0.20568 x 10⁷ m⁻¹
λ = 4.86 x 10⁻⁷ m
since 1 m = 10⁹ nm
λ = 486 nm
Lewis had proposed that the valence electrons of any substance were arranged around its atoms in a cubic configuration. Later on, this was modified when it was learned that the electrons actually orbit the nucleus, similar to the planets orbiting the sun. Moreover, it is now deduced that the electrons are found in regions, known as electron clouds, and their specific, discrete location at a given point in time can not be determined.