Answer:
Option B. 450mL
Explanation:
To obtain the volume of water that must be added, we need to First find the volume of the diluted solution.
C1 (concentration of the stock solution) = 8M
V1 (volume of the stock solution) = 150mL
C2 (concentration of the diluted solution) = 2M
V2 (volume of the diluted solution) =?
Using the dilution formula C1V1 = C2V2, we can obtain the volume of the diluted solution as follow:
C1V1 = C2V2
8 x 150 = 2 x V2
Divide both side by 2
V2 = (8 x 150)/2
V2 = 600mL
The volume of water added is simply the difference between the volume of the diluted solution and that of the stock solution. This is illustrated below
Volume of water added = V2 - V1 = 600 - 150 = 450mL
Answer:
In order to prepare 200.0 mL of an aqueous solution of iron (III) chloride, at a concentration of 1.25 x 10⁻² M, you need to weight 0.4055 g of FeCl₃ and add to 200.0 mL of water.
Explanation:
Concentration: 1.25 x 10⁻² M
1,25 x 10⁻² mol FeCl₃ ___ 1000 mL
x ___ 200.0 mL
x = 2.5 x 10⁻³ mol FeCl₃
Mass of FeCl₃:
1 mol FeCl₃ _____________ 162.2 g
2.5 x 10⁻³ mol FeCl₃ _______ y
y = 0.4055 g FeCl₃
The wavelength of the photon required to excite this molecule from its ground state, to its first excited state is 1240 nm.
This is given by the equation:
wavelength = hc/(E_homo - E_lumo)
where h is Planck's constant =6.626070 * 10^-34 J.m , c is the speed of light = 3.0 x 10^8 m/s^2, and E_homo and E_lumo are the energies of the highest occupied molecular orbital and the lowest unoccupied molecular orbital, respectively.
In this particular case, the wavelength of the required photon would be:
wavelength = hc/(-2.42 hartree - 0.65 hartree)
= 6.626070 * 10^-34 X 3.0 x 10^8 / (-3.07)
= 1240 nm
Hence , The wavelength of the photon required to excite this molecule from its ground state, to its first excited state is 1240 nm.
Learn more about wavelength at : brainly.com/question/13533093
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Answer: experiments are use to test if an hypothesis is right or wrong
Explanation:
