An earthquake is a catastrophic<span> event that results from a gradual accumulation of stresses at fault lines. Clearly </span>catastrophism<span> is at work.</span>
Answer:
there is no d electron that can be promoted via the absorption of visible light
Explanation:
One of the properties of transition elements is the possession of incompletely filled d orbitals. This property accounts for their unique colours.
The colours of transition metal compounds stem from d-d transition of electrons due to the presence of vacant d orbitals of appropriate energy to which electrons could be promoted.
For elements whose atoms have a d10 configuration, such vacant orbitals does not exist hence their compounds are not colored.
Sometimes, the colour of transition metal compounds stem from ligand to metal charge transfer(LMCT) for instance in KMnO4.
<u>Answer:</u>
<u>For A:</u> The
for the given reaction is 
<u>For B:</u> The
for the given reaction is 1642.
<u>Explanation:</u>
The given chemical reaction follows:

The expression of
for the above reaction follows:

We are given:

Putting values in above equation, we get:

Hence, the
for the given reaction is 
Relation of
with
is given by the formula:

where,
= equilibrium constant in terms of partial pressure = 
= equilibrium constant in terms of concentration = ?
R = Gas constant = 
T = temperature = 500 K
= change in number of moles of gas particles = 
Putting values in above equation, we get:

Hence, the
for the given reaction is 1642.
Answer:
The net ionic equation is
C6H5COOH+ CN-= C6H5COO- + HCN
Explanation:
From the ionic equation
C6H5COOH + Na+ + CN- = C6H5COO- + Na+ + HCN
Only sodium is the spectator ion, so it cancels out, since C6H5COOH and HCN do not ionize completely they are left undissociated