The most stable isotope would be lead-82.
A law is statement about an observed concept. A theory involves the explanation of scientific concepts or principles. A hypothesis is the predicted explanation about some concepts that has to be tested in order to prove it to be right. An observation is the observing the results of a scientific experiment carried out to test an hypothesis.
Here the given statement 'A chemist mixes sodium with water and witnesses a violent reaction between the metal and water,' can be classified as an observation as it explains what the chemists observes as a result of his chemical experiment or test..
The process where fossil fuels, forests, or other carbon-containing substances are burned, addin more carbon dioxide to the air is the combustion.
Some examples of combustion are:
Fossil fuel:
Carbon + O2
C + O2 -> CO2
Forests (wood)
Wood = cellulose = [C6H10O5]n
[C6H10O5]n + 6nO2 = 6n CO2 + 5n H2O
So, in general the combustion of organic matter produces CO2 and water.
The answer is c because of going left to right
