An atom has 13 protons and 14 neutrons. what is its mass number?
1 answer:
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Answer:
Explanation:
Use one of your experimentally determined values of k, the activation energy you determined, and the Arrhenius equation to calculate the value of the rate constant at 25 °C. Alternatively, you can simply extrapolate the straight line plot of ln(k) vs. 1/T in your notebook to 1/298 , read off the value of ln(k), and determine the value of k. Please put your answer in scientific notation. slope=-12070, Ea=100kJ/mol, k= 0.000717(45C), 0.00284(55C), 0.00492(65C), 0.0165(75C), 0.0396(85C)
Explanation;
According to Arrhenius equation:
i.e. ln(k2/k1) = -Ea/R (1/T2 - 1/T1)
Where, k1 = 0.000717, T1 = 45 oC = (45+273) K = 318 K
T2 = 25 oC = (25 + 273) K = 298 K
i.e. ln(k2/0.000717) = -12070 (1/298 - 1/318)
i.e. ln(k2/0.000717) = -2.54738
i.e. k2/0.000717 =
= 0.078286
Therefore, the required constant (k2) = 0.078286 * 0.000717 =
Answer:
0.2g
Explanation:
Given parameters:
Number of moles of H₂ = 0.4mol
Number of moles of O₂ = 0.15mol
Unknown:
Mass of reactant that would remain = ?
Solution:
To solve this problem, we need to know the limiting reactant which is the one in short supply in the given reaction.
The expression of the reaction is :
2H₂ + O₂ → 2H₂O
2 mole of H₂ will combine with 1 mole of O₂
But given; 0.4 mole of H₂ we will require = 0.2mole of O₂
The given number of oxygen gas is 0.15mole and it is the limiting reactant.
Hydrogen gas is in excess;
1 mole of oxygen gas will combine with 2 mole of hydrogen gas
0.15 mole of oxygen gas will require 0.15 x 2 = 0.3mole of hydrogen gas
Now, the excess mole of hydrogen gas = 0.4 mole - 0.3 mole = 0.1mole
Mass of hydrogen gas = number of mole x molar mass
Molar mass of hydrogen gas = 2(1) = 2g/mol
Mass of hydrogen gas = 0.1 x 2 = 0.2g