Hertz is units for frequency. (waves per second)
wavelength = speed/frequency
if you're given the speed use that to calculate, if not then you can probably assume it's a wave of light and use the speed of light (3x10^8 m/s) to calculate.
wavelength = (3x10^8)/(1.28x10^17)
= 0.000000002 m
= 2.34 nm
I believe the answer is D) 2
Answer:
Moles of
= 6 moles
Explanation:
The reaction of
and
to make
is:
⇒
The above reaction shows that 2 moles of Sc can react with 3 moles of
to form 
Mole Ratio= 2:3
For 10 moles of Sc we need:
Moles of
= 
Moles of
= 
Moles of
=15 moles
So 15 moles of
are required to react with 10 moles of
but we have 9 moles of
, it means
is limiting reactant.


Moles of ScCl_3= 6 moles
This happens because ice is made up of water, and when that water freezes, it never goes back to land, thus there being less water on the coastline. But when the ice starts to melt, the water will even out quickly, and the water will go to the coastline, causing the tide to rise. Mark brainliest, please.