Answer:
mix 1 mL of the stock solution of MgCl2, 300 mL of the stock solution of NaCl and 699 mL of water.
Explanation:
We need to determine the volume necessary of both stock solutions. When a dilution is made, a certain volume of the stock solution is collected and then more solvent is added to it until the volume is completed. So, the number of moles of the solute in both solutions are the same, and it is the concentration (C) multiplied by the volume (V). If 1 is the stock solution and 2 the diluted solution:
C1*V1 = C2*V2
So, in this case, the two solutions will be mixed, and then the volume will be completed with the solvent. So, for MgCl2:
C1 = 1.0 M
C2 = 1.0 mM = 0.001 M
V2 = 1.0 L = 1000 mL
1*V1 = 0.001*1000
V1 = 1 mL of the stock solution of MgCl2
For NaCl:
C1 = 0.50 M
C2 = 0.15 M
V2 = 1000 mL
0.50*V1 = 0.15*1000
V1 = 300 mL
So, it will be necessary 1 mL of the stock solution of MgCl2, 300 mL of the stock solution of NaCl and 699 mL of water.
Answer:
A. ![\lambda_0=2.196\times 10^{-7}\ m](https://tex.z-dn.net/?f=%5Clambda_0%3D2.196%5Ctimes%2010%5E%7B-7%7D%5C%20m)
Explanation:
The work function of the Platinum =
For maximum wavelength, the light must have energy equal to the work function. So,
Where,
h is Plank's constant having value
c is the speed of light having value
is the wavelength of the light being bombarded
Thus,
![\frac{9.05}{10^{19}}=\frac{19.878}{10^{26}\lambda_0}](https://tex.z-dn.net/?f=%5Cfrac%7B9.05%7D%7B10%5E%7B19%7D%7D%3D%5Cfrac%7B19.878%7D%7B10%5E%7B26%7D%5Clambda_0%7D)
![9.05\times \:10^{26}\lambda_0=1.9878\times 10^{20}](https://tex.z-dn.net/?f=9.05%5Ctimes%20%5C%3A10%5E%7B26%7D%5Clambda_0%3D1.9878%5Ctimes%2010%5E%7B20%7D)
![\lambda_0=2.196\times 10^{-7}\ m](https://tex.z-dn.net/?f=%5Clambda_0%3D2.196%5Ctimes%2010%5E%7B-7%7D%5C%20m)
Assume that the concentration of stock is 1.0 M
And initial volume = 16.0 ml
final volume = 0.310 L or 310 ml
therefore
CiVi = CfVf
1.0 *16 ml = Cf * 310 ml
Cf = 1.0*16/310
= 0.052 M
Thus dilute solution is 0.052 M times dilute to concentrate solution
The answer is B as isotopes are different versions of the same chemical element containing the same amount of protons and electrons but different amounts of neutrons.
Answer:
kilogram ;)) The kilogram is the standard