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:
Explanation:
Na react with H2O to form NAOH
2 Na+2H2O....................2NAOH + H2
Ca react with water and form calcium hydroxide
Ca + 2H2O........................Ca(OH)2
Mg react with water and form Magnesium hydroxide
Mg +2H2O .........................Mg(OH)2 however this coating of mg(oh)2 prevent it from further reaction
Fe react with water and form ferric hydride
3Fe +H2O.......................2 FeH +FeO
copper do not react with water
Using ideal gas equation,

Here,
P denotes pressure
V denotes volume
n denotes number of moles of gas
R denotes gas constant
T denotes temperature
The values at STP will be:
P=1 atm
T=25 C+273 K =298.15K
V=663 ml=0.663L
R=0.0821 atm L mol ⁻¹
Mass of gas given=1.25 g g
Molar mass of gas given=?


Putting all the values in the above equation,

Molar mass of the gas=46.15
3.6 x 10^-4
I am writing this sentence because the answer does not reach the 20 character limit. Thank you have nice day! :D Cx :P
Sodium reacts to chlorine and gives NaCl. The balanced reaction is given below:
2Na + Cl₂→ 2NaCl. Two moles Na reacts with one mole Cl₂ and produces two moles of NaCl. Atomic mass of Na= 23, Molar mass of Cl₂= 71, molar mass of NaCl=58.5.
So, 46 g Na reacts with 71 g of Cl₂ and produces (2 X 58.5)g = 117 g of NaCl. As per question Na reacts completely which means Na is the limiting reagent. So, number of moles of Na reacts = number moles of NaCl produced.
NaCl produced= 819 g= (819/58.5) moles= 15.69 moles. Therefore, 15.69 moles = 15.69 X 23 g=360.87 g of Na reacted.