The rate constant (k) for a reaction was measured as a function of temperature. a plot of lnk versus 1/t(in k) is linear and has
1 answer:
The Arrhenius equation is
so if we plot a graph between lnK (natural log of rate constant) and 1/T (inverse of temperature in kelvin)
The straight line equation will be
lnK = lnA - Ea/RT
Where
A = constant for a particular reaction at any temperature
R = gas constant = 8.314 J /molK
So as per this equation the slope of line will be = -Ea/R
Or
Ea = -slope X R
Ea = -(-9.20X10³X 8.314) =76.49kJ /mol
Answer: activation energy = 76.49 kJ /mol
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Answer:
1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.
Explanation:
The balanced reaction is:
Mg+ 2 HCl → MgCl₂ + H₂
By stoichiometry of the reaction, the following amounts of moles of each compound participate in the reaction:
- Mg: 1 mole
- HCl: 2 moles
- MgCl₂: 1 mole
- H₂: 1 mole
Being the molar mass of each compound:
- Mg: 24.31 g/mole
- HCl: 36.45 g/mole
- MgCl₂: 95.21 g/mole
- H₂: 2 g/mole
By reaction stoichiometry, the following mass amounts of each compound participate in the reaction:
- Mg: 1 mole* 24.31 g/mole= 24.31 g
- HCl: 2 moles* 36.45 g/mole= 72.9 g
- MgCl₂: 1 mole* 95.21 g/mole= 95.21 g
- H₂: 1 mole* 2 g/mole= 2 g
Then you can apply the following rule of three: if by stoichiometry 24.31 grams of Mg produces 2 grams of H₂, 12.5 grams of Mg produces how much mass of H₂?
mass of H₂= 1.03 grams
<u><em>1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.</em></u>