Question

how are the frequency and wavelength of light related?
they are directly proportional to each other.
wavelength is determined by dividing frequency by the speed of light.
they are inversely proportional to each other.
frequency equals wavelength divided by the speed of light.
question 18 (1 point)
as changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit
increase.
cannot be determined.
decrease.
remain the same.
question 19 (1 point)
what is another name for the representative elements?
group a elements
transition elements
group c elements
group b elements

Explanation:

• For the first question: The relationship between frequency ($

u$) and wavelength ($\lambda$) of light is given by the formula $c = \lambda
u$, where $c$ is the speed of light (a constant). Rearranging gives $\lambda=\frac{c}{
u}$, showing an inverse - proportionality.

• For the second question: The energy of a photon is $E = h

u$, where $h$ is Planck's constant. As the change in energy levels ($\Delta E$) of electrons increases, and $\Delta E=E = h
u$, the frequency $
u$ of the emitted atomic line spectra increases.

• For the third question: Representative elements are also known as Group A elements in the older (American) group - numbering system for the periodic table. Transition elements are in the d - block, and there is no standard "Group C" or "Group B" (in the context of representative elements) nomenclature for representative elements.

Answer:

• First question: C. They are inversely proportional to each other.
• Second question: A. increase.
• Third question: A. Group A elements.