Answer:
Fossils are the some traces or portions of the animals or plants, buried and preserved from past in rocks, sediments or ice.
Explanation:
Correct match is as follows-
- Mold and cast fossils- An organism is buried in sediment after it dies.The hard part of organism leave behind a empty space imprinted in the rock. Later sediments and minerals fill the space and harden to make the original copy of the organisms.
- Carbon film fossils- An organism buried in sediments gets squeezed and heated inside the earth , leaving behind a thin carbon outline of the organism on a rock.
- Amber fossil- An organism covered in tree resin or tree sap , which then hardens with the body of the organisms preserved inside.
- Ice fossil- An organism dies in a cold place on earth , its body becomes frozen and covered in layers of ice . The hard and soft part of the body may be preserved.
Answer:
Titration is a technique to determine the concentration of an unknown solution. As illustrated in the titration setup above, a solution of known concentration (titrant) is used to determine the concentration of an unknown solution (titrand or analyte).
Typically, the titrant (the solution of known concentration) is added through a burette to a known volume of the analyte (the solution of unknown concentration) until the reaction is complete. Knowing the volume of titrant added allows us to determine the concentration of the unknown analyte. Often, an indicator is used to signal the end of the reaction, the endpoint. Titrant and analyte is a pair of acid and base. Acid-base titrations are monitored by the change of pH as titration progresses.
Let us be clear about some terminologies before we get into the discussion of titration curves.
Gases<span> in the </span>atmosphere<span> such as carbon dioxide </span>do<span> what the roof of a </span>greenhouse does. Earth's<span> surface warms up in the sunlight. At night, </span>Earth's surface cools, releasing the heat back into the air. The gases involved in the greenhouse effect are carbon dioxide<span>, </span>methane<span>, </span>nitrous oxide<span>, </span>halocarbons<span>, chlorofluorocarbons, </span>water vapor<span>, and </span>ozone<span>. These gases are all in Earth's atmosphere.</span>
P1V1=P2V2
SO
2X0.140=P2X4.50
P2=2X0.140/4.50
P2=0.0622 atm
