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siniylev [52]
3 years ago
15

The fossil record is the record of life on earth preserved in rock as fossils. The fossil record provides evidence of what types

of plant and animals lived, how long they lived, how they died, and changed. It also tells us about Earth’s early environment, and how it changed. The fossil record helps determine the age of rock formations by looking at how deep the fossil are buried in the rock. When a fossil is found above another fossil in a rock formation, the deeper fossil are considered older.
What can scientists infer about a specific period of Earth's history if many fossils were discovered from oxygen-breathing organisms?
A) the atmosphere lacked oxygen
B) only fish lived during that time
C) the dinosaurs used all the oxygen
D) the atmosphere had lots of oxygen
Chemistry
2 answers:
Yuki888 [10]3 years ago
5 0

Answer:

the correct answer is d)

Explanation:

strojnjashka [21]3 years ago
3 0

Answer:

d is wrong the correct answer is b

Explanation:

The atmosphere lacked oxygen is correct. The lack of animals that used oxygen suggests that the environment did not have much oxygen.

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Can you identify a chemical only by knowing its physical properties?
amid [387]

Answer:

Any characteristic that can be determined without changing the substance's chemical identity. chemical property: Any characteristic that can be determined only by changing a substance's molecular structure

Explanation:

4 0
3 years ago
Water molecules stick together by a force called?
patriot [66]

Answer:

Cohesion

Explanation:

Depending on how attracted molecules of the same substance are to one another, the substance will be more or less cohesive. Hydrogen bonds cause water to be exceptionally attracted to each other. Therefore, water is very cohesive.

8 0
4 years ago
Read 2 more answers
Which of the fallowing elements would be least reactive a) iodine b) silicon c) silver d) argon
damaskus [11]

Answer:

Noble Gases

Explanation:It's not on there but Noble gases is the least reactive element because it has 8 electrons and their outer energy is full.

5 0
3 years ago
Suppose a healthy individual experiences a surge in plasma calcium. subsequently, where would one expect to find the greatest am
victus00 [196]

One can expect to find the greatest amount of hydrolyzed pth when, entering the nephrons.

<h3><u>Where would one expect to find the greatest amount of hydrolyzed pth ?</u></h3>
  • In a healthy person, the body will respond by excreting calcium and PTH byproducts if plasma calcium is higher than usual. The nephron is a solid predictor since the kidneys are where excretion takes place.
  • A) is false since PTH, not the hydrolyzed compounds, is produced by the parathyroid gland.
  • One would anticipate significant amounts of PTH exiting the liver rather than entering since the liver hydrolyzes PTH.
  • The largest concentration would still be in the nephrons, even if it is possible that some hydrolysis products will be in systemic circulation (and therefore penetrate the bones).
  • The cortical bone, which is the outermost part of the bone, has a network of small tubes called haversian canals that let blood vessels and nerves to pass through them.

To view more about hydrolyzed pth, refer to:

brainly.com/question/4765096

#SPJ4

8 0
1 year ago
0.100 mol of CaCO3 and 0.100 mol CaO are placed in an 10.0 L evacuated container and heated to 385 K. When equilibrium is reache
astra-53 [7]

Answer:

10.32g

Explanation:

First thing's first, lets bring out the balanced chemical equation representing the reaction.

CaCO3(s) ⇄ CaO(s) + CO2(g)

From the question;

reaction constant K = [CO2(g)] = 0.220 atm.

To obtain number of moles of CO2, using ideal gas fomula, we have;

n = PV/RT = 0.220*10 / (0.08206*385) = 0.0696(mol)

From the stoichiometry of the equation above;

This is the amount of CaCO3 which has been converted to CaO before additional 0.230 atm CO2(g) is added.

After the additional 0.230 atm CO2(g), the equilibrium CO2 pressure is still 0.220 atm.  Therefore all this additional CO2 would completely convert to CaCO3:

n = PV/RT = 0.230*10.0/(0.08206*385) = 0.0728 (mol)

Hence the total CaCO3 after equilibrium is reestablished is:

0.100 - 0.0696 + 0.0728 (mol) = 0.1032 mol

Mass = Number of moles * Molar mass

Mass = 0.1032 * 100 = 10.32g

7 0
3 years ago
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