<u>Answer:</u> The number of electrons for n = 0, 1 and 2 are 2, 6 and 10 respectively.
<u>Explanation:</u>
Huckel's rule is used to determine the aromaticity in a compound. The number of delocalized
electrons are calculated by using the equation:

where,
n = 0 or any whole number
- Calculating the value of electrons for n = 0
Putting values in above equation, we get:

- Calculating the value of electrons for n = 1
Putting values in above equation, we get:

- Calculating the value of electrons for n = 2
Putting values in above equation, we get:

Hence, the number of electrons for n = 0, 1 and 2 are 2, 6 and 10 respectively.
Answer:
Thomson placed two magnets on either side of the tube, and observed that this magnetic field also deflected the cathode ray. The results of these experiments helped Thomson determine the mass-to-charge ratio of the cathode ray particles, which led to a fascinating discovery, minus the mass of each particle was much, much smaller than that of any known atom. Thomson repeated his experiments using different metals as electrode materials, and found that the properties of the cathode ray remained constant no matter what cathode material they originated from. From this evidence, Thomson made the following conclusions:
The cathode ray is composed of negatively-charged particles.
The particles must exist as part of the atom, since the mass of each particle is only ~1/2000 the mass of a hydrogen atom.
These subatomic particles can be found within atoms of all elements.
While controversial at first, Thomson's discoveries were gradually accepted by scientists. Eventually, his cathode ray particles were given a more familiar name: electrons. The discovery of the electron disproved the part of Dalton's atomic theory that assumed atoms were indivisible. In order to account for the existence of the electrons, an entirely new atomic model was needed.
Explanation:
<span>Since,
1000 grams of water = 1000 mL of water</span><span>
So,
At any of the given temperature:
</span>1000 mL = 10 x 100 mL
<span>
moles of NH4Cl = 53.5/53.49
= 1.0 m
= 1.0 mol/Kg
Delta T = 2 x 1.86 x 1.0
= 3.72 c
= - 3.72 °C</span>
0001 M HCl is the same as saying that 1 *10-4 moles of H+ ions have been added to solution. The -log[. 0001] =4, so the pH of the solution =4.