Answer:
Its D :)
<em>Or not i haven't done this in a while-</em>
The question is incomplete, the complete question is;
In the 1800s, a popular belief known as vitalism stated that life processes could not be explained by the laws of physics and chemistry,and were instead dictated by an independent life force. Which discovery most likely caused scientists to revise this hypothesis regarding the origin of life on Earth?
a. that inorganic compounds existed within live organisms
b. that organic compounds could be synthesized in a laboratory
c. that RNA could serve as a template to synthesize DNA
d. that self-replicating molecules existed inside cells
Answer:
b. that organic compounds could be synthesized in a laboratory
Explanation:
Vitalism is the belief that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things"(wikipedia).
This theory held that the molecules involved in life processes could not be synthesized in the laboratory.
All these were upturned after Fredrich Whöler's synthesis of urea in 1828. He was able to show that molecules involved in life process can also be synthesized in the laboratory. This gave rise to modern synthetic organic chemistry.
Answer:
Option (2) 2
Explanation:
NO3- + 4H+ + Pb → Pb2+ + NO2 + 2H2O
The equation above can be balance as follow:
There are 3 atoms of the left side and a total of 4 atoms on the right side. It can be balance by putting 2 in front NO3- and 2 in front of NO2 as shown below:
2NO3- + 4H+ + Pb → Pb2+ + 2NO2 + 2H2O
Now the equation is balanced.
The coefficient of NO2 is 2
b,f,h are already balanced
