Given the half life of the first order decomposition reaction is 355 s
Rate constant of the first order reaction is related to the half life by the equation,
k = 0.00195 
The concentration of the substance is decreased to 1/4 th.
If we start with 1 M solution, after time t the concentration becomes 1/4th = 0.25 M
First order rate law:
![[A] = [A]_{0} e^{-kt}](https://tex.z-dn.net/?f=%20%5BA%5D%20%3D%20%5BA%5D_%7B0%7D%20e%5E%7B-kt%7D%20%20)
![[A] = 0.25 M](https://tex.z-dn.net/?f=%20%5BA%5D%20%3D%200.25%20M%20)
![[A]_{0} = 1 M](https://tex.z-dn.net/?f=%20%5BA%5D_%7B0%7D%20%3D%201%20M%20)
Plugging in the values to solve for t,
t = 710 s
Answer:
1.0 x 10⁻⁹ M OH⁻.
Explanation:
∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.
[H₃O⁺] = 1.0 x 10⁻⁵ M.
<em>∴ [OH⁻] = 10⁻¹⁴/[H₃O⁺] </em>= 10⁻¹⁴/(1.0 x 10⁻⁵ M) = <em>1.0 x 10⁻⁹ M.</em>
<em>So, the right choice is: 1.0 x 10⁻⁹ M OH⁻.</em>
LiOH+HCL LiCL+H2O represents a double replacement reaction.
The answer is B
To write the equilibrium constant for an equation, all you have to do is divide the products by the reactants. The reactants are always on the left side, and the products are always on the right side. The coefficients of the elements will be written as the exponent of that same element. However, in this equation, we do not have to write any exponents, as there are no coefficient but 1.
