<u>Answer:</u> The longest wavelength of light is 656.5 nm
<u>Explanation:</u>
For the longest wavelength, the transition should be from n to n+1, where: n = lower energy level
To calculate the wavelength of light, we use Rydberg's Equation:

Where,
 = Wavelength of radiation
 = Wavelength of radiation
 = Rydberg's Constant  =
 = Rydberg's Constant  = 
 = Higher energy level =
 = Higher energy level = 
 = Lower energy level = 2    (Balmer series)
= Lower energy level = 2    (Balmer series)
Putting the values in above equation, we get:

Converting this into nanometers, we use the conversion factor:

So, 
Hence, the longest wavelength of light is 656.5 nm
 
        
             
        
        
        
Faster molecules have fewer collisions than slower molecules is True about molecular speed.
<h3>What is Molecular speed?</h3>
Molecular speed refers to the average distance gases or molecules travelled atca particular time rate.
It is valid in ideal gas, where the molecules do not interact with others.
Average molecular speed = Square root (3 (ideal gas constant) * (Temperature)/m)
Therefore, Faster molecules have fewer collisions than slower molecules is True about molecular speed.
Learn more about molecular speed from the link below.
brainly.com/question/14327643
  
        
             
        
        
        
<u>Answer:</u> The net ionic equation for the given reaction is 
<u>Explanation:</u>
Net ionic equation of any reaction does not include any spectator ions.
Spectator ions are the ions which do not get involved in a chemical equation. It is also defined as the ions that are found on both the sides of the chemical reaction when it is present in ionic form.
The chemical equation for the reaction of hydrochloric acid and potassium sulfite is given as:

Ionic form of the above equation follows:

As, potassium and chloride ions are present on both the sides of the reaction, thus, it will not be present in the net ionic equation.
The net ionic equation for the above reaction follows:

Hence, the net ionic equation for the given reaction is written above.
 
        
             
        
        
        
The gram-formula mass of Sm is 150.36 u, and the gram-formula mass of O is 15.999 u, so the gram-formula mass of SmO is about 150.36+15.999 = 160.36 g/mol.
So, there are about (9.30 * 10^-3)(160.36)=1.49 grams