Answer:
Mass of chemical = 1.5 mg
Explanation:
Step 1: First calculate the concentration of the stock solution required to make the final solution.
Using C1V1 = C2V2
C1 = concentration of the stock solution; V1 = volume of stock solution; C2 = concentration of final solution; V2 = volume of final solution
C1 = C2V2/V1
C1 = (6 * 25)/ 0.1
C1 = 1500 ng/μL = 1.5 μg/μL
Step 2: Mass of chemical added:
Mass of sample = concentration * volume
Concentration of stock = 1.5 μg/μL; volume of stock = 10 mL = 10^6 μL
Mass of stock = 1.5 μg/μL * 10^6 μL = 1.5 * 10^6 μg = 1.5 mg
Therefore, mass of sample = 1.5 mg
Answer:
Hi there!
The correct answer to this question is: electrons enter orbitals of lowest energy first.
Answer:
It takes 5.83s to decrease the concentration of the reactant from 0.537M to 0.100M
Explanation:
A zero-order reaction follows the equation:
[A] = [A]₀ - kt
<em>Where [A] is actual reaction of the reactant = 0.100M</em>
<em>[A]₀ the initial concentration = 0.537M</em>
<em>k is rate constant = 0.075Ms⁻¹</em>
<em>And t is time it takes:</em>
<em />
0.100M = 0.537M -0.075Ms⁻¹t
-0.437M = -0.075Ms⁻¹t
5.83s = t
It takes 5.83s to decrease the concentration of the reactant from 0.537M to 0.100M
Answer:
2.32 m
Explanation:
So, according to definition of mole fraction:

Mole fraction = 0.176
Applying values as:


So,



Also, Molar mass of toluene = 92.14 g/mol
Thus,
The formula for the calculation of moles is shown below:


Also, 1 g = 0.001 kg
So,

Molality is defined as the moles of the solute present in 1 kg of the solvent.
It is represented by 'm'.
Thus,

<u>Molality of benzene = 2.32 m</u>