Answer:- 0.00724 moles.
Solution:- Grams of salicylic acid are given and it asks to calculate the moles.
For the moles, we divide the grams by the molar mass.
Formula of salicylic acid is ![C_7H_6O_3](https://tex.z-dn.net/?f=C_7H_6O_3)
Molar mass = 7(12.01)+6(1.01)+3(16.00)
= 84.07+6.06+48.00
= 138.13 gram per mol
We could make the dimensional analysis set up for showing unit cancellation and have the moles.
![1.00g(\frac{1mol}{138.13g})](https://tex.z-dn.net/?f=1.00g%28%5Cfrac%7B1mol%7D%7B138.13g%7D%29)
= 0.00724 moles
So, there will be 0.00724 moles of salicylic acid in it's 1.00 gram.
E = hf
c = speed of electromagnetic wave, c ≈ 3 * 10⁸ m/s,
Planck's constant h = 6.63 *10⁻³⁴ Js
h = Planck's constnat, Frquency, f = c/λ = (3*10⁸)/(488*10⁻⁹)
E = hf
E = hc/λ
E = (6.63 * 10⁻³⁴ * 3 * 10⁸) /(488 * 10⁻⁹)
Energy, E ≈ 4.0758 * 10⁻¹⁹ Joules.
Answer:
Solar energy absorbed at Earth’s surface is radiated back into the atmosphere as heat. As the heat makes its way through the atmosphere and back out to space, greenhouse gases absorb much of it. Why do greenhouse gases absorb heat? Greenhouse gases are more complex than other gas molecules in the atmosphere, with a structure that can absorb heat. They radiate the heat back to the Earth's surface, to another greenhouse gas molecule, or out to space.
There are several different types of greenhouse gases. The major ones are carbon dioxide, water vapor, methane, and nitrous oxide. These gas molecules all are made of three or more atoms. The atoms are held together loosely enough that they vibrate when they absorb heat. Eventually, the vibrating molecules release the radiation, which will likely be absorbed by another greenhouse gas molecule. This process keeps heat near the Earth’s surface. Most of the gas in the atmosphere is nitrogen and oxygen, which cannot absorb heat and contribute to the greenhouse effect.
Explanation:
D=mxv so your answer should be 269.37
The given question is incomplete. The complete question is:
When 136 g of glycine are dissolved in 950 g of a certain mystery liquid X, the freezing point of the solution is 8.2C lower than the freezing point of pure X. On the other hand, when 136 g of sodium chloride are dissolved in the same mass of X, the freezing point of the solution is 20.0C lower than the freezing point of pure X. Calculate the van't Hoff factor for sodium chloride in X.
Answer: The vant hoff factor for sodium chloride in X is 1.9
Explanation:
Depression in freezing point is given by:
= Depression in freezing point
= freezing point constant
i = vant hoff factor = 1 ( for non electrolyte)
m= molality =![\frac{136g\times 1000}{950g\times 75.07g/mol}=1.9](https://tex.z-dn.net/?f=%5Cfrac%7B136g%5Ctimes%201000%7D%7B950g%5Ctimes%2075.07g%2Fmol%7D%3D1.9)
![8.2^0C=1\times K_f\times 1.9](https://tex.z-dn.net/?f=8.2%5E0C%3D1%5Ctimes%20K_f%5Ctimes%201.9)
Now Depression in freezing point for sodium chloride is given by:
= Depression in freezing point
= freezing point constant
m= molality =
![20.0^0C=i\times 4.32^0C\times 2.45](https://tex.z-dn.net/?f=20.0%5E0C%3Di%5Ctimes%204.32%5E0C%5Ctimes%202.45)
![i=1.9](https://tex.z-dn.net/?f=i%3D1.9)
Thus vant hoff factor for sodium chloride in X is 1.9