Quantitative observation have accuracy over qualitative observation as in Quantitative observation data is recorded in terms of number .
Explanation:
Qualitative observations are descriptive observations that don't involve numbers. " The freezing point of water is colder than the boiling point " is an example. Quantitative observations are numerical measurements. "The freezing point of watrr is 0 c and boiling point is 100 c" is a quantitative observation.
A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms
Answer: a) pH = 13.00 : basic
b)
: basic
c) pOH = 5.00 : basic
d)
: acidic
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H_3O^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH_3O%5E%2B%5D)
Acids have pH ranging from 1 to 6.9 and bases have pH ranging from 7.1 to 14.Neutral substances have pH of 7.
a) pH = 13.00
As pH is more than 7, the solution is basic.
b) ![[H_3O^+]=1.0\times 10^{-12}](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%3D1.0%5Ctimes%2010%5E%7B-12%7D)
Putting in the values:
![pH=-\log[1.0\times 10^{-12}]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B1.0%5Ctimes%2010%5E%7B-12%7D%5D)

As pH is more than 7, the solution is basic.
c) pOH = 5.00


As pH is more than 7, the solution is basic.
d) ![[OH^-]=1.0\times 10^{-9}](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D1.0%5Ctimes%2010%5E%7B-9%7D)
Putting in the values:
![pOH=-\log[1.0\times 10^{-9}]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%5B1.0%5Ctimes%2010%5E%7B-9%7D%5D)



As pH is less than 7, the solution is acidic.
Formal charge can be calculated from the following formula
Formal charge = valency of central atom - (number of lone pair of electrons + number of covalent bonds)
a) for methylene:
Formal charge = 4 -( 2+ 2) = 0
b) For methyl free radical
Formal charge = 4- (3 +1) = 0