The answer is going to be 476.06.
Answer: 159 grams
Explanation:
Copper (ii) oxide has the chemical formula CuO.
Now given that:
Mass of CuO in grams = ? (let unknown value be Z)
Number of moles = 2.00 moles
Molar mass of CuO = ?
For the molar mass of CuO: Atomic mass of Copper = 63.5g ; Oxygen = 16g
= 63.5g + 16g
= 79.5 g/mol
Apply the formula:
Number of molecules = (mass in grams/molar mass)
2.00 moles = (Z / 79.5 g/mol)
Z = 79.5 g/mol x 2.00 moles
Z = 159g
Thus, there are 159 grams in 2.00 moles of copper (ii) oxide
The correct option is this: THE CONCENTRATION OF THE PRODUCTS AND THE REACTANTS DO NOT CHANGE.
A reversible chemical reaction is said to be in equilibrium if the rate of forward reaction is equal to the rate of backward reaction. At this stage, the concentrations of the products and the reactants remain constant, that is, there is no net change in the concentration even though the reacting species are moving between the forward and the backward reaction.
Answer:
A = 1,13x10¹⁰
Ea = 16,7 kJ/mol
Explanation:
Using Arrhenius law:
ln k = -Ea/R × 1/T + ln(A)
You can graph ln rate constant in x vs 1/T in y to obtain slope: -Ea/R and intercept is ln(A).
Using the values you will obtain:
y = -2006,9 x +23,147
As R = 8,314472x10⁻³ kJ/molK:
-Ea/8,314472x10⁻³ kJ/molK = -2006,9 K⁻¹
<em>Ea = 16,7 kJ/mol</em>
Pre-exponential factor is:
ln A = 23,147
A = e^23,147
<em>A = 1,13x10¹⁰</em>
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I hope it helps!
Answer:
Considering the half-life of 10,000 years, after 20,000 years we will have a fourth of the remaining amount.
Explanation:
The half-time is the time a radioisotope takes to decay and lose half of its mass. Therefore, we can make the following scheme to know the amount remaining after a period of time:
Time_________________ Amount
t=0_____________________x
t=10,000 years____________x/2
t=20,000 years___________x/4
During the first 10,000 years the radioisotope lost half of its mass. After 10,000 years more (which means 2 half-lives), the remaining amount also lost half of its mass. Therefore, after 20,000 years, the we will have a fourth of the initial amount.
