To find the atomic mass of chlorine, the atomic mass of each isotope is multiplied by the relative abundance (the percent abundance in decimal form) and then the individual masses are added together. The atomic mass of chlorine is 35.45 amu.
Answer: 15.0 moles of
are formed from 30.0 mol of 
Explanation:
The balanced chemical reaction is :
According to stoichiometry :
2 moles of
give = 1 mole of 
Thus 30.0 moles of
will give =
of 
Thus 15.0 moles of
are formed from 30.0 mol of 
Answer:
Difference between concentrated acid and weak acid :---
- According to Arrhenius's theory the substances which easily get dissociated into H+ ions when dissolved in water are acids.
- And the substance which readily gives H+ ions on dissociation (when dissolved in water) are Strong Acid. Examples are HCl , H2SO4 etc.
While,
- Concentration of acid is just the value of pH. pH is the measurement of concentration of acid or base. The lower the pH, higher the concentration.
- So strong acid is strong because it gives H+ ions readily in water and Concentration is the value of pH.
I think it is the gas and the heat in it