<u>Answer:</u> The rate constant for the given reaction is 
<u>Explanation:</u>
For the given chemical equation:
We are given that the above equation is undergoing first order kinetics.
The equation used to calculate rate constant from given half life for first order kinetics:
The rate constant is independent of the initial concentration for first order kinetics.
We are given:
= half life of the reaction = 
Putting values in above equation, we get:
Hence, the rate constant for the given reaction is
Answer:
<h2>4.0 </h2>
Explanation:
The pH of a solution can be found by using the formula
![pH = - log [ { H}^{+}]](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5B%20%7B%20H%7D%5E%7B%2B%7D%5D)
From the question we have
We have the final answer as
<h3>4.0</h3>
Hope this helps you
Answer: The answer to the first one is the second option and the answer for the second one is the first option.
Explanation:
Answer:
6.4 × 10^-10 M
Explanation:
The molar solubility of the ions in a compound can be calculated from the Ksp (solubility constant).
CaF2 will dissociate as follows:
CaF2 ⇌Ca2+ + 2F-
1 mole of Calcium ion (x)
2 moles of fluorine ion (2x)
NaF will also dissociate as follows:
NaF ⇌ Na+ + F-
Where Na+ = 0.25M
F- = 0.25M
The total concentration of fluoride ion in the solution is (2x + 0.25M), however, due to common ion effect i.e. 2x<0.25, 2x can be neglected. This means that concentration of fluoride ion will be 0.25M
Ksp = {Ca2+}{F-}^2
Ksp = {x}{0.25}^2
4.0 × 10^-11 = 0.25^2 × x
4.0 × 10^-11 = 0.0625x
x = 4.0 × 10^-11 ÷ 6.25 × 10^-2
x = 4/6.25 × 10^ (-11+2)
x = 0.64 × 10^-9
x = 6.4 × 10^-10
Therefore, the molar solubility of CaF2 in NaF solution is 6.4 × 10^-10M
