Answer:
Mass of hydrogen gas evolved is 0.0749 grams.
Explanation:
Total pressure of the gases = p = 758 mmHg
Vapor pressure of water = 23.78 mmHg
Pressure of hydrogen gas ,P = p - 23.78 mmHg = 758 mmHg - 23.78 mmHg
P = 734.22 mmHg = 
Temperature of of hydrogen gas ,T= 25°C =298.15 K
Volume of hydrogen gas = V = 0.949 L
Moles of hydrogen gas =n
PV = nRT (Ideal gas equation )

n = 0.03745 mol
Moles of hydrogen gas = 0.03745 mol
Mass of 0.03745 moles of hydrogen gas = 0.03745 mol × 2 g/mol = 0.0749 g
Mass of hydrogen gas evolved is 0.0749 grams.
I don't know if this is the answer you are looking for but it would be flat unless the player pushed the tuning slide in.
Answer:
Cracking.
Explanation:
A chemical reaction can be defined as a reaction in which two or more atoms of a chemical element react to form a chemical compound. An example of a chemical reaction involving hydrocarbons is cracking.
Hydrocarbon can be defined as an organic compound that comprises of hydrogen and carbon only.
In Organic chemistry, cracking refers to the process of lowering the boiling point of a heavy, complex or long-chain hydrocarbon such as kerogens by exposing it to different environmental treatments such as hydrogen enriched catalysts, pressure or high temperatures, in order to produce smaller, lighter and more useful molecules (alkanes and alkenes) such as gasoline, diesel fuel, etc.
Answer: 63.26%
Explanation:
If we let the abundance of the first isotope be x, then:

Which is equal to <u>63.26%</u>