Answer : The Lewis-dot structure of
is shown below.
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, 
As we know that hydrogen has '1' valence electron and nitrogen has '5' valence electrons.
Therefore, the total number of valence electrons in
= 5 + 3(1) = 8
According to Lewis-dot structure, there are 6 number of bonding electrons and 2 number of non-bonding electrons.
Now we have to determine the formal charge for each atom.
Formula for formal charge :





Hence, the Lewis-dot structure of
is shown below.
<u>Answer:</u> The correct answer is Option 4.
<u>Explanation:</u>
Bromothymol blue, Bromocresol green and Thymol blue are the indicators which change their color according to the change in pH of the solution.
The pH range and color change of these indicators are:
- Bromothymol Blue: The pH range for this indicator is 6.0 to 7.5 and color change is from yellow to blue. It appears yellow below pH 6.0 and blue above pH 7.5
- Bromocresol green: The pH range for this indicator is 3.5 to 6.0 and color change is from yellow to blue. It appears yellow below pH 3.5 and blue above pH 6.0
- Thymol Blue: The pH range for this indicator is 8.0 to 9.6 and color change is from yellow to blue. It appears yellow below pH 8.0 and blue above pH 9.6
As, the highest pH of all the indicators is 9.6, so every indicator will appear blue above pH 9.6.
Hence, the correct answer is Option 4.
1) This is a definition.
2) Protons are given by the bottom number (since atomic number = number of protons).
3) Neutrons = (mass number)-(atomic number), which are the top and bottom numbers, respectively.
4) Nuclear fusion involves combining two things together, which is only reflected by the last option.
5) This is a fact.
6) This is a fact.
7) This is a fact.
8) This is a fact.
9) The correct option is the explanation.
<u>Answer:</u> The number of
ions dissociated are
<u>Explanation:</u>
We are given:
pH = 2.07
Calculating the value of pOH by using equation, we get:

To calculate hydroxide ion concentration, we use the equation to calculate pOH of the solution, which is:
![pOH=-\log[OH^-]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%5BOH%5E-%5D)
We are given:
pOH = 11.93
Putting values in above equation, we get:
![11.93=-\log[OH^-]](https://tex.z-dn.net/?f=11.93%3D-%5Clog%5BOH%5E-%5D)
![[OH^-]=10^{-11.93}=1.17\times 10^{-12}M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D10%5E%7B-11.93%7D%3D1.17%5Ctimes%2010%5E%7B-12%7DM)
To calculate the number of moles for given molarity, we use the equation:

Molarity of solution = 
Volume of solution = 1243 mL = 1.243 L (Conversion factor: 1 L = 1000 mL)
Putting values in above equation, we get:

According to mole concept:
1 mole of a compound contains
number of particles
So,
number of
will contain =
number of ions
Hence, the number of
ions dissociated are