Answer:
The steps with correct mechanism are given below:
C
1) CH₄(g) + Cl(g) → CH₃(g) + HCl(g) : This is a slow step.
The rate is given as: R1 = k₁[CH₄][Cl]
2) CH₃(g) + Cl₂(g) → CH₃Cl(g) + Cl(g): This is a fast step.
The rate is given as: Rate = k₂[CH₃][Cl₂]
∴ CH₄(g) + Cl₂(g) → CH₃Cl(g) + HCl(g)
Here, the slowest step will be the rate-determining step.
Answer:
Boron (B) Atomic Mass: 10.811
Explanation:
The number of protons and electrons are the same, always. You can find the atomic mass by looking at the periodic table for that atom: 10.811
Answer:
pH =3.8
Explanation:
Lets call the monoprotic weak acid HA, the dissociation equilibria in water will be:
HA + H₂O ⇄ H₃O⁺ + A⁻ with Ka = [ H₃O⁺] x [A⁻]/ [HA]
The pH is the negative log of the H₃O⁺ concentration, we know the equilibrium constant, Ka and the original acid concentration. So we will need to find the [H₃O⁺] to solve this question.
In order to do that lets set up the ICE table helper which accounts for the species at equilibrium:
HA H₃O⁺ A⁻
Initial, M 0.40 0 0
Change , M -x +x +x
Equilibrium, M 0.40 - x x x
Lets express these concentrations in terms of the equilibrium constant:
Ka = x² / (0.40 - x )
Now the equilibrium constant is so small ( very little dissociation of HA ) that is safe to approximate 0.40 - x to 0.40,
7.3 x 10⁻⁶ = x² / 0.40 ⇒ x = √( 7.3 x 10⁻⁶ x 0.40 ) = 1.71 x 10⁻³
[H₃O⁺] = 1.71 x 10⁻³
Indeed 1.71 x 10⁻³ is small compared to 0.40 (0.4 %). To be a good approximation our value should be less or equal to 5 %.
pH = - log ( 1.71 x 10⁻³ ) = 3.8
Note: when the aprroximation is greater than 5 % we will need to solve the resulting quadratic equation.
Answer:
because they devlop our organs
The charge of a Rb ion would be +1
