This is given by Avogagro number: 1 mol = 6.02*10^23 particles
Then you can do whichever to these two relations, because they are equivalent:
- 1mol / 6.02*10^23 representative particles, and
- 6.02*10^23 representative particle /1 mol
Only the second option of the question includes one of the valid conversion factors. Then, the conversion factor of the second option is the right answer
climate
Changes in the composition of the atmosphere have caused gradual changes in earth's <u>climate</u> throughout history, causing changes in plant and animal life that contributed to mass extinctions.
The following are some of the reasons:
- UV light
- climate
- pollutants
- hydrofluorocarbons
heat
- The surface of the Earth warms up as sunlight strikes it.
- Surface-emitted infrared light is absorbed in the atmosphere and transformed into heat.
- The temperature close to the surface rises as a result of this heat being trapped in the atmosphere.
<h3>UV light:</h3>
- indirect impacts of climate change on UV radiation from the surface.
- By changing the concentrations of ozone, UV-absorbing tropospheric gases, aerosols, and clouds in the atmosphere, climate change may have indirectly affected UV radiation levels in the past.
- These influences are probably going to persist in the future.
<h3>climate:</h3>
- People are at risk from food and water shortages, greater flooding, high heat, an increase in disease, and economic loss due to climate change.
- Conflict and human migration are potential outcomes.
- Climate change is the top hazard to world health in the twenty-first century, according to the World Health Organization (WHO).
<h3>pollutants:</h3>
- these are also resulting in the increase of temperature of the Earth and is also damaging ozone layer.
To learn more about the changes in earth visit:
brainly.com/question/13434833?
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Answer:
11.39
Explanation:
Given that:


Given that:
Mass = 1.805 g
Molar mass = 82.0343 g/mol
The formula for the calculation of moles is shown below:

Thus,


Given Volume = 55 mL = 0.055 L ( 1 mL = 0.001 L)


Concentration = 0.4 M
Consider the ICE take for the dissociation of the base as:
B + H₂O ⇄ BH⁺ + OH⁻
At t=0 0.4 - -
At t =equilibrium (0.4-x) x x
The expression for dissociation constant is:
![K_{b}=\frac {\left [ BH^{+} \right ]\left [ {OH}^- \right ]}{[B]}](https://tex.z-dn.net/?f=K_%7Bb%7D%3D%5Cfrac%20%7B%5Cleft%20%5B%20BH%5E%7B%2B%7D%20%5Cright%20%5D%5Cleft%20%5B%20%7BOH%7D%5E-%20%5Cright%20%5D%7D%7B%5BB%5D%7D)

x is very small, so (0.4 - x) ≅ 0.4
Solving for x, we get:
x = 2.4606×10⁻³ M
pOH = -log[OH⁻] = -log(2.4606×10⁻³) = 2.61
<u>pH = 14 - pOH = 14 - 2.61 = 11.39</u>