The below is about the energy exchanges in earth systems.
<u>Explanation</u>:
- Energy exchanges in earth systems are of many types. The earth systems are atmosphere, geosphere, stratosphere, hydrosphere, and biosphere. All these earth systems exchange energy with each other.
- The earth gains energy reflected from the sky. It converts that energy back to space. That energy is equally given to all the planets in the sky.
- Each planet will absorb that energy and radiate heat. This heat is absorbed by all the places on the earth. So this is the energy exchange in the earth systems.
<h3>Answer:</h3>
a) Moles of Caffeine = 1.0 × 10⁻⁴ mol
b) Moles of Ethanol = 4.5 × 10⁻³ mol
<h3>Solution:</h3>
Data Given:
Mass of Caffeine = 20 mg = 0.02 g
M.Mass of Caffeine = 194.19 g.mol⁻¹
Molecules of Ethanol = 2.72 × 10²¹
Calculate Moles of Caffeine as,
Moles = Mass ÷ M.Mass
Putting values,
Moles = 0.02 g ÷ 194.19 g.mol⁻¹
Moles = 1.0 × 10⁻⁴ mol
Calculate Moles of Ethanol as,
As we know one mole of any substance contains 6.022 × 10²³ particles (atoms, ions, molecules or formula units). This number is also called as Avogadro's Number.
The relation between Moles, Number of Particles and Avogadro's Number is given as,
Number of Moles = Number of Molecules ÷ 6.022 × 10²³
Putting values,
Number of Moles = 2.72 × 10²¹ Molecules ÷ 6.022 × 10²³
Number of Moles = 4.5 × 10⁻³ Moles
They can use them to find the age of fossils.
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The answer to your question is,
B. Government.
-Mabel <3