Answer:
Here's what I get.
Explanation:
(b) Wavenumber and wavelength
The wavenumber is the distance over which a cycle repeats, that is, it is the number of waves in a unit distance.
Thus, if λ = 3 µm,
(a) Wavenumber and frequency
Since
λ = c/f and 1/λ = f/c
the relation between wavenumber and frequency is
Thus, if f = 90 THz
(c) Units
(i) Frequency
The units are s⁻¹ or Hz.
(ii) Wavelength
The SI base unit is metres, but infrared wavelengths are usually measured in micrometres (roughly 2.5 µm to 20 µm).
(iii) Wavenumber
The SI base unit is m⁻¹, but infrared wavenumbers are usually measured in cm⁻¹ (roughly 4000 cm⁻¹ to 500 cm⁻¹).
Answer:4
Explanation:
As shown in the image attached, a face-centred cubic structure has 8 atoms at the corners and 6 face center atoms.
Each corner atom contributes to eight cell, so per unit cell 1/8 ×8 =1atom
Face center atoms contributes to two unit cells 1/2 × 6=3atoms
Total atoms =3+1=4atoms
Therefore the atoms in Al FCC per unit cell is 4
The HCl added = 1.25 moles
and the moles of Na2HPO4 = 1 mole
Now when acid is added in the given solution of Na2HPO4
One mole of H+ will react with one mole of Na2HPO4 to given one mole of NaH2PO4
Na2HPO4 + H+ ---> NaH2PO4
Now this one mole formed NaH2PO4 will further react with 0.25 moles of H+ left to form 0.25 moles of H3PO4 and 0.75 moles of NaH2PO4 will remain in the solution
So this will result into formation of a buffer of phosphoric acid and NaH2PO4
NaH2PO4 + H+ ---> H3PO4
pKa of H3PO4 = 2.1
so pH = pKa + log [salt] / [acid] = 2.1 + log [0.75 / 0.25] = 2.58
so the pH will be in between 2.1 to 7.2
Answer:
The only one that makes sense IF the model behaves as the Earth is D.
Explanation:
Hey Madoudou
The correct answer is option B (sulfate)
The reason is because "Sulfate" has a negative sign.
In order for it to be a cation, it must have positive sign such as "iron(lll)ion
I hope this helps~
