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:
pH is calculated by taking negative logarithm of hydrogen ion concentration. Acids have pH ranging from 1 to 6.9, bases have pH ranging from 7.1 to 14 and neutral solutions have pH equal to 7. Thus the sum of pH and pOH is 14
Explanation:
The statement that best describes how an ionic compound dissolves in water is as follows: it separates into individual molecules and is an electrolyte, which is option C.
<h3>What is an ionic compound?</h3>
Ionic compound is any compound is a chemical compound composed of ions (charged atoms) held together by electrostatic forces termed ionic bonding.
Ionic compounds are electrolytes i.e. a substance when, in solution or when molten, ionizes and conducts electricity.
For example; sodium chloride (NaCl) is an ionic compound breaks down into sodium ions (Na+) and chloride ion (Cl-).
Therefore, the statement that best describes how an ionic compound dissolves in water is as follows: it separates into individual molecules and is an electrolyte.
Learn more about ionic compound at: brainly.com/question/9167977
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Answer:
A synthetic element is one of 24 chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made".
Explanation: hope that helps
