# The second-order reaction 2 Mn(CO)5 → Mn2(CO)10, has a rate constant equal to 3.0 × 109 M-1 s-1 at 25°C. If the initial concentration of Mn(CO)5 is 2.0 × 10-5 M, how long will it take for 90.% of the reactant to disappear?

t = 1.5 E-4 s

Explanation:

• 2 Mn(CO)5 → Mn2(CO)10
• - ra = K(Ca)∧α = - δCa/δt

∴ a: Mn(CO)5

∴ K = 3.0 E9 M-1 s-1................rate constant

∴ T = 25°C

∴ α = 2................ second-order

∴ Cao = 2.0 E-5 M................initial concentration

If  Ca = Cao - (Cao×0.90) ⇒ t = ?

⇒ Ca = 2.0 E-5 - ((2.0 E-5)(0.90)) = 2.0 E-6 M

⇒ - δCa/δt = KCa²

⇒ - ∫δCa/Ca² = K∫δt

⇒ [(1/Ca) - (1/Cao)] = K*t

⇒ t = [(1/Ca) - (1/Cao)] / K

⇒ t = [ (1/2 E-6) - (1/2 E-5)] / (3.0 E9)

⇒ t = 1.5 E-4 s

## Related Questions

HURRY PLEASE Which descriptions apply to Mendel’s pea plant experiments? CHECK ALL THAT APPLIES PLEASE

1. studied first generation plants only

2. relied on random pollination and reproduction of plants

3. used cross breeding to purposely breed plants

4. studied a variety of pea plant traits

5. focused primarily on breeding larger, healthier pea plants

6. studied several generations of plants

3. used cross breeding to purposely breed plants

4. studied a variety of pea plant traits

6. studied several generations of plants

Explanation:

Known as the father of genetics, Gregor Johann Mendel was born in what is now the Czech Republic. He entered the monastery at a young age, and there he learned agrarian sciences and various techniques of artificial pollination, which allowed the crossing of various plant species. Through his experiments, Mendel discovered and answered several questions about heredity. We can state that Mendel's experiments used crossbreeding to purposely create plants, studied a variety of pea plant characteristics, and studied several generations of plants.

3. used cross breeding to purposely breed plants
4. studied a variety of pea plant traits
6. studied several generations of plants

Determine the moles of H+ reacting with the metal based on the following experimental data. 10.00 mL of 1.00 M HCl solution is added to a sample of Mg metal. The reaction goes to completion and all of the Mg metal is gone. 27.08 mL of 0.30 M NaOH solution is required to reach the end point when titrating the remaining HCl.

Approximately .

Explanation:

Convert both volumes to standard units (that is: liters.)

• .
• .

Number of moles of initially present (in the solution at .)

.

Number of moles of from the titration:

.

neutralizes at a ratio:

.

Hence, .

.

If kc = 0.143 at 25°c for this reaction, predict the direction in which the system will shift if the initial concentrations of c6h12 and mcp are 0.400 m and 0.300 m, respectively. the system

The equation is as follows:
Cyclohexane (C6H12) ⇔ Methyl cyclopentane (C6H12)
The equilibrium constant Kc = 0.143 >>> (1)
Qc is the reaction quotient
where; If Q = K >>>> No shift left or right >>> (2)
Q > K >>>> Reaction shifts left >>> (3)
Q < K >>>> Reaction shifts right >>> (4)
And in our equation; Q = 0.3 / 0.4 = 0.75 >>> (5)
From (1), (3) and (5), Q > Kc
∴ the reaction shifts left

All atoms of an element always have the same number of A Protons

B Neutrons

C Electrons

D Electrons