Answer:
1.58x10⁻⁵
2.51x10⁻⁸
0.0126
63.10
Explanation:
Phenolphthalein acts like a weak acid, so in aqueous solution, it has an acid form HIn, and the conjugate base In-, and the pH of it can be calculated by the Handerson-Halsebach equation:
pH = pKa + log[In-]/[HIn]
pKa = -logKa, and Ka is the equilibrium constant of the dissociation of the acid. [X] is the concentrantion of X. Thus,
i) pH = 4.9
4.9 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = - 4.8
[In-]/[HIn] = 
[In-]/[HIn] = 1.58x10⁻⁵
ii) pH = 2.1
2.1 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -7.6
[In-]/[HIn] = 
[In-]/[HIn] = 2.51x10⁻⁸
iii) pH = 7.8
7.8 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -1.9
[In-]/[HIn] = 
[In-]/[HIn] = 0.0126
iv) pH = 11.5
11.5 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = 1.8
[In-]/[HIn] = 
[In-]/[HIn] = 63.10
Answer:
See explanation
Explanation:
Polymerization is the process whereby two or more monomers link together to form a compound of high molecular mass called a polymer.
There are two kinds of polymers;
-Addition polymers
-Condensation polymers
Addition polymers are formed by the joining of two or more monomers to form a polymer without the elimination of a small molecule.
Condensation polymers are formed by the joining of two or more molecules to form polymers with the elimination of a small molecule.
The main difference between polyethene and polyester is that polyethene is an addition polymer while polyester is a condensation polymer.
In polyethene, ethene molecules are joined together having the repeating unit as [-CH2-CH2-]n.
In polyester, the polymer arises from the reaction of carboxylic acid and an alcohol and loss of water molecules.
Answer:
the answer is According to this model, the atom is a sphere of positive charge, and negatively charged electrons are embedded in it to balance the total positive charge. The electrons are like plums in a pudding.
Explanation: