Explanation:
from the graph study about oxygen content of Earth's atmosphere, we can understand that
1)
4 billions year ago = None, 3 billions year ago = Cyanobacteria and Archaea , 2 and 1 billions year ago = Bacteria and Green algae , 500 Ma = invertebrate fossils started to existence. Early land plants came in to existence around 398 MA that is Devonian. Dinosaurs are came in to existence during Triassic and Jurassic that is around 251 Ma. Man and animals are recent organism came under Holocene that is 11000 years ago.
2)
The first cells on the earth are anaerobic microorganisms, as the CO2 level is too high they survive by using CO2.
3)
Starting around 2.7 billion years ago, photosynthesis by Cyanobacteria and later plants , pumped “OXYGEN” in to the atmosphere. This caused the decline of anaerobic bacteria and allows the diversification of animals as seen in “CAMBRIAN” around 500 millions year ago.
Early vascular plants “CAPTURED” CO2 starting before the Carboniferous period that began around 350 millions year.Leading to lower temperatures and allowing and allowing the seed plants to outcompetes seedless plants.
Modern human activities has raised both “CO2 and METHANE” level in the atmosphere to over leading to higher temperature and extinction of other species.
Answer: a.KOH
Potassium hydroxide is an ionic compound where the K+ is the cation and OH−is the anion. At the same time, the compound also contains a covalent bond since the anion, OH−is formed from electron sharing between the O and H atoms.
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Explanation:
Increase in heat, molecules start to escape and it turns to vapor
Answer: The concentrations of A , B , and C at equilibrium are 0.1583 M, 0.2583 M, and 0.1417 M.
Explanation:
The reaction equation is as follows.
Initial : 0.3 0.4 0
Change: -x -x x
Equilbm: (0.3 - x) (0.4 - x) x
We know that, relation between standard free energy and equilibrium constant is as follows.
Putting the given values into the above formula as follows.
x = 0.1417
Hence, at equilibrium
= 0.1583 M
= 0.2583 M
Answer:
From the periodic table:
mass of carbon = 12 grams
mass of hydrogen = 1 grams
mass of oxygen = 16 grams
molar mass of surcose = 12(12) + 22(1) + 11(16) = 342 grams
number of molecules = number of moles x Avogadro's number
number of moles = number of molecules / Avogadro's number
number of moles = (2.2x10^17) / (6.02x10^23) = 3.6544 x 10^-7 moles
number of moles = mass / molar mass
mass = number of moles x molar mass
= 1.7 x 10^17/6.022 x 10^23.
