Answer:
Endothermic
Explanation:
The temperature of the water decreased.
The water lost heat.
The heat must have gone into getting the KNO₃ into solution.
So, the dissolving of KNO₃ in water is endothermic.
4.1 h = 14760 s
<span>t 1/2 = ln 2 / k </span>
<span>k = rate reaction = 4.97 x 10^-5 </span>
<span>ln 0.045 / 0.36 = - 4.97 x 10^-5 t </span>
<span>2.08 = 4.97 x 10^-5 t </span>
<span>t = 41839.9 s = 11 h 37 min 19 s</span>
Answer:
A. CsBr(s)
Explanation:
we will get here compound with the lowest lattice energy
solution
As we know that Lattice energy is always proportional to the charge of ions and it is inversely proportional to the size of ions.
so that by the smallest charge and the largest size give us the lowest lattice energy and that charge and size is express as here as
Charge
Cs (+1), K(+1), Na (+1), Cl(-1), Br(-1), Sr(+2), Ca(+2), O(-2) .......................1
and
Size
Na+ < Ca2+ < K+ < Sr2+ < Cs+, O2- < Cl- < Br- ..........................2
so that here
correct answer is A. CsBr
Explanation:
The given data is as follows.
(NaCl) = 
(H-O=C-ONO) = 
(HCl) = 
Conductivity of monobasic acid is 
Concentration = 0.01 
Therefore, molar conductivity (
) of monobasic acid is calculated as follows.

= 
= 
= 
Also,
= 
= 
= 
Relation between degree of dissociation and molar conductivity is as follows.

= 
= 0.1254
Whereas relation between acid dissociation constant and degree of dissociation is as follows.
K = 
Putting the values into the above formula we get the following.
K = 
= 
= 
= 
Hence, the acid dissociation constant is
.
Also, relation between
and
is as follows.

= 
= 3.7454
Therefore, value of
is 3.7454.