Answer:
Option c: Possible electron energy states are quantized within an atom.
Explanation:
The Bohr's Model of the hydrogen atom consisted of the movements of the electrons around the positively-charged nucleus in circular orbits that have a certain energy state. The energy of that orbit is given by:

<em>Where:</em>
E(n): is the energy of an electron in a particular orbit
R: is the Rydberg constant
h: is the Plank constant
c: is the speed of light
n: is a positive integer which corresponds to the number of the orbit
The ground state energy of a electron in the hydrogen atom is equal to -13,6 eV.
Bohr's Model aims to propose that the electron is restrictedly to occupy a certain region in the atom.
Therefore, the conclusion of Bohr after observing emission spectrum lines is that "possible electron energy states are quantized within an atom", so the correct option is c.
I hope it helps you!
The answer is the mass number! (:
Answer : Methanal also known as Formaldehyde
is a chemical Aldehyde which contain ( -CHO) group.
Explanation :
In organic chemistry, a carbonyl group is a functional group which contain a carbon atom double-bonded to an oxygen atom i.e, ( C=O).
If carbonyl group is present in a compound then it can be a carboxylic (RCOOH), aldehyde (RCHO), ketone (RCOR'), ester ((RCOOR') or amide (RCONR'R") group.
Here are some functional groups naming according to the<em> IUPAC</em> rules and image also attached,
Carboxylic acid → (RCOOH) → ( name end in 'OIC ACID' )
Aldehyde → (RCOH) → ( name end in 'AL' )
Ketone → (RCOR') → ( name end in 'ONE' )
Ester → (RCOOR') → ( name end in 'ATE' )
Amide → (RCONR'R") → ( name end in 'AMIDE' )
In an aldehyde, atleast one hydrogen atom must be attached to the carbonyl carbon. For an aldehyde, remove ( -e) from alkane name and add ( -al) at the end of the compound.
Methanal is the IUPAC name for Formaldehyde.
Chemical sanitizer effectiveness, decreases with increase in pH . And most soap and detergent are alkaline in nature, that limits its effectiveness. So they should be rinsed off completely for proper effectiveness of santizer. So improper rinsing limits the effectiveness of a sanitizer.
So , the answer is improper rinsing after that still a detergent residue remains limits the effectiveness of sanitizer.