Answer:
D. 18,800 J/mol
Explanation:
We need to use the Arrhenius equation to solve for this problem:
, where k is the rate constant, A is the frequency factor,
is the activation energy, R is the gas constant, and T is the temperature in Kelvins.
We want to find the value of
, so let's plug some of the information we have into the equation. The gas constant we can use here is 8.31 J/mol-K.
At 0°C, which is 0 + 273 = 273 Kelvins, the rate constant k is
. So:


At 20°C, which is 20 + 273 = 293 Kelvins, the rate constant k is
. So:


We now have two equations and two variables to solve for. We just want to find Ea, so let's write the first equation for A in terms of Ea:


Plug this in for A in the second equation:


After some troublesome manipulation, the answer should come down to be approximately:
Ea = 18,800 J/mol
The answer is thus D.
Answer: C) Bent or angular, polar
Explanation:
The central atom oxygen has two lone pairs and two bond pairs in . The number of electron pairs are 4, that means the hybridization will be and the electronic geometry of the molecule will be tetrahedral. But as there are two lone pair of atoms around the central oxygen atom, repulsion between lone and bond pair of electrons is more and hence the molecular geometry will be bent shape.
The compound is polar as the net dipole moment of oxygen - fluoride bonds do not cancel each other out.
The frequency of radiation : 1.2 x 10¹⁵ Hz
<h3>Further explanation
</h3>
Radiation energy is absorbed by photons
The energy in one photon can be formulated as

Where
h = Planck's constant (6,626.10⁻³⁴ Js)
f = Frequency of electromagnetic waves
<h3>f = c / λ
</h3>
c = speed of light
= 3.10⁸ m/s
λ = wavelength
Wavelength-λ is 2.51 x 10⁻⁷m
The frequency :

Half-life is the time required for the amount of something to fall to half its initial value. This term is usually used in nuclear physics to describe how quickly unstable atoms undergo decay, or how long stable atoms survive, radioactive decay, and it is also used more generally of any type of exponential or non-exponential decay.
In simpler terms: this is when an isotopes radioactivity is cut in half
The answer is <span>0.000261 millimeters</span>