Answer:
a. 750Hz, b. 4.0ppm, c. 600Hz
Explanation:
The Downfield Shift (Hz) is given by the formula
Downfield Shift (Hz) = Chemical Shift (ppm) x Spectrometer Frequency (Hz)
Using the above formula we can solve all three parts easily
a. fspec = 300 MHz, Chem. Shift = 2.5ppm, 1MHz = 10⁶ Hz, 1ppm (parts per million) = 10⁻⁶
Downfield Shift (Hz) = 2.5ppm x 300MHz x (1Hz/10⁶MHz) x (10⁻⁶/1ppm)
Downfield Shift = 750 Hz
The signal is at 750Hz Downfield from TMS
b. Downfield Shift = 1200 Hz, Chemical Shift = ?
Chemical Shift = Downfield shift/Spectrometer Frequency
Chemical Shift = (1200Hz/300MHz) x (1ppm/10⁻⁶) = 4.0 ppm
The signal comes at 4.0 ppm
c. Separation of 2ppm, Downfield Shift = ?
Downfield Shift (Hz) = 2(ppm) x 300 (MHz) x (1Hz/10⁶MHz) x (10⁻⁶/1ppm) = 600 Hz
The two peaks are separated by 600Hz
The major force between ethanol and rubbing alcohol is hydrogen bond. Hydrogen bond are intermolecular force that are weaker than covalent bond but holds atoms together in a molecules. For an hydrogen bond to be formed, a molecule must contain an hydrogen atom that will be bonded to one of the most electronegative element.
Answer:
Molality = <u>10.300 m</u>
<u>Molarity = 6.5970 M</u>
<u>mole fraction = </u>0.156549
Explanation:
39.0 % = ethylene glycol
61.0 % = water
imagine the total mass = 100g
39.0% ethylene glycol = 39g
61.0 % water = 61g
1) Molality = number of moles / mass of solvent (kg)
Molar mass of ethylene glycol = 62.07g/mole
mole = 39g / 62.07g/mole = 0.6283 moles
Molality = moles / mass of solvent = 0.6283 moles / 0.061kg = <u>10.300 m</u>
<u />
<u>2) Molarity</u> = number of moles / volume of solution
Since we know the density of the solution = 1.05g /ml
⇒ volume = 100g / 1.05g /mL = 95.24 mL = 0.09524 L
Molarity = 0.6283 moles / 0.09524 L = <u>6.5970 M</u>
3) Mole fraction
moles water = 61g / 18.02g/mole = 3.38513 moles
Total number of moles = moles of ethylene glycol + moles of water = 0.6283 + 3.38513 = 4.0134276 moles
Mole fraction = 0.6283/ 4.0134276 = 0.156549
An ionic compound is made up of a metal and a nonmetal. This eliminates answer choice A, C, and D because both of the elements listed are nonmetal.
Your correct answer is B) One atom of calcium and two atoms of chlorine. This is because calcium is a metal, and chlorine is a nonmetal.
In 1 molecule of the compound C₆H₁₂O₂ there are 12 moles of hydrogen atoms
<h3>Further explanation</h3>
Given
C₆H₁₂O₂ compound
Required
moles of Hydrogen
Solution
In a compound, there is a mole ratio of the constituent elements.
The empirical formula is the smallest comparison of atoms of compound forming elements.
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
In the C₆H₁₂O₂ compound, there are 3 forming elements: C, H and O
The number of each element is indicated by its subscript
C: 6 moles
H = 12 moles
O = 2 moles
