Answer:
81.71%
Explanation:
One mole of propane contains 3 moles of carbon atoms and 8 moles of hydrogen atoms, as seen from the molecular formula of
. In order to calculate the percent of carbon in propane by mass, we need to remember that %w/w (or percent mass) formula states that:

That is, we need to divide the mass of the component of interest by the total mass of the compound and multiply by 100 to obtain the percentage.
For simplicity, let's take 1 mole of propane and find the mass of 1 mole (hence, we'll be finding the molar mass of propane). To do that, we add the 3 molar masses of carbon and 8 molar masses of hydrogen to obtain a total of:

Now that we have the molar mass of propane, we also need to find the total mass of carbon in 1 mole of propane. We know that we have a total of 3 moles of carbon which corresponds to:

Dividing the mass of carbon present by the total mass of the compound will yield the mass percentage as defined by the formula we introduced:

Answer:
The correct answer to the following question will be "NaCl".
Explanation:
- A solute is being known as the soluble material within a liquid or a solution. The solvent is available in larger quantities than those of the solute among fluid.
- Concentration seems to be a calculation including its quantity of solvent contained in such a liquid solution, regard to something like the solvent volume.
So that NaCl is the right answer.
The symbols indicate the physical state of each reactant
Answer:
they often use a radon detector to help forecast earthquakes
Answer:
the radioactive half-life of an atom can depend on how it is bonded to other atoms. by changing the neighboring atoms that are bonded to a radioactive isotope, we can change its half-life.
Explanation: