Answer:
Molar mass→ 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Explanation:
Let's apply the formula for freezing point depression:
ΔT = Kf . m
ΔT = 74.2°C - 73.4°C → 0.8°C
Difference between the freezing T° of pure solvent and freezing T° of solution
Kf = Cryoscopic constant → 5.5°C/m
So, if we replace in the formula
ΔT = Kf . m → ΔT / Kf = m
0.8°C / 5.5 m/°C = m → 0.0516 mol/kg
These are the moles in 1 kg of solvent so let's find out the moles in our mass of solvent which is 0.125 kg
0.0516 mol/kg . 0.125 kg = 6.45×10⁻³ moles. Now we can determine the molar mass:
Molar mass (mol/kg) → 0.930 g / 6.45×10⁻³ mol = 144.15 g/mol
Answer:
The catalyzed reaction will take 2.85 seconds to occur.
Explanation:
The activation energy of a reaction is given by:
For the reaction without catalyst we have:
(1)
And for the reaction with the catalyst:
(2)
Assuming that frequency factor (A) and the temperature (T) are constant, by dividing equation (1) with equation (2) we have:
Since the reaction rate is related to the time as follow:
![k = \frac{\Delta [R]}{t}](https://tex.z-dn.net/?f=%20k%20%3D%20%5Cfrac%7B%5CDelta%20%5BR%5D%7D%7Bt%7D%20)
And assuming that the initial concentrations ([R]) are the same, we have:
![\frac{k_{1}}{k_{2}} = \frac{\Delta [R]/t_{1}}{\Delta [R]/t_{2}}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bk_%7B1%7D%7D%7Bk_%7B2%7D%7D%20%3D%20%5Cfrac%7B%5CDelta%20%5BR%5D%2Ft_%7B1%7D%7D%7B%5CDelta%20%5BR%5D%2Ft_%7B2%7D%7D%20)
Therefore, the catalyzed reaction will take 2.85 seconds to occur.
I hope it helps you!
Answer:
50g
Explanation:
pls mark me brainliest right
The sedimentary rock formed when water deposits tiny particles of clay in very thin flat layers is called limestone.
The modern day model of an atom has a lot of questions answered about it answered and is very accurate while John's version was a very early model before technology was advanced enough to get more information on it so it was very basic and not as accurate as today's model. Hope this helps!
