Answer: Electronegativity increases as the size of an atom decrease.
Explanation: Electronegativity is the measure of the ability of an atom in a bond to attract electrons to itself.
Electronegativity increases across a period and decreases down a group.
Towards the left of the table, valence shells are less than half full, so these atoms (metals) tend
to lose electrons and have low electronegativity. Towards the right of the table, valence shells are more than half full, so these atoms (nonmetals) tend to gain electrons and have high electronegativity.
Down a group, the number of energy levels (n) increases, and so does the distance between the nucleus and the outermost orbital. The increased distance and the increased shielding weaken the nuclear attraction, and so an atom can’t attract electrons as strongly.
Hey there!
Values Ka1 and Ka2 :
Ka1 => 8.0*10⁻⁵
Ka2 => 1.6*10⁻¹²
H2A + H2O -------> H3O⁺ + HA⁻
Ka2 is very less so I am not considering that dissociation.
Now Ka = 8.0*10⁻⁵ = [H3O⁺] [HA⁻] / [H2A]
lets concentration of H3O⁺ = X then above equation will be
8.0*10−5 = [x] [x] / [0.28 -x
8.0*10−5 = x² / [0.28 -x ]
x² + 8.0*10⁻⁵x - 2.24 * 10⁻⁵
solve the quardratic equation
X =0.004693 M
pH = -log[H⁺]
pH = - log [ 0.004693 ]
pH = 2.3285
Hope that helps!
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
A catalyst is defined as the substance which increases the rate of the reaction without actually participating in the reaction.
This substance decreases the activation energy of the reactants, so as to proceed the reaction at a faster rate by increasing their effective collisions.
It does not affect the concentration of the reactants.
For the given reaction:

If we add NO, which is acting as a catalyst will increase the rate of the reaction to produce the products which is 
Hence, the correct answer is Option A.
Answer:
E) rate of appearance of C = 0.45 M/s
rate of the reaction = 0.15 M/s
Explanation:
2A + B → 3C
Writing rate law for the reaction:
<u>Rate of reaction</u> = -
= -
= 
→ equation 1
Given that the rate of disappearance of A is 0.3 M/s
⇒ -
= 0.3 M/s
⇒Rate of reaction = - 
=
×0.3 M/s
⇒<u>Rate of reaction = 0.15 M/s</u>
From equation 1,
= - 
=
×0.3 M/s
⇒
= 0.45 M/s
or <u>the rate of appearance of C = 0.45 M/s</u>