Luminosity is the amount of energy emitted by a star each second. Stars radiate light over a broad range of frequencies in the electromagnetic spectrum, <span>from the low energy radio waves to high energy gamma rays. Energy emitted from stars is the result of fusion of gases within its core</span>
Answer:
0.50 moles of Cu
Explanation:
The balanced chemical equation for given synthetic reaction is,
2 Cu + S → Cu₂S
According to balance chemical equation,
1 mole of Cu₂S is produced by = 2 moles of Cu
So,
0.25 moles of Cu₂S will be produced by = X moles of Cu
Solving for X,
X = 0.25 mol × 2 mol / 1 mol
X = 0.50 moles of Cu
Hence, as the molar ratio of Cu to Cu₂S is 2:1 hence, to produce 0.25 moles of Cu₂S we will need 0.50 moles of Cu.
1) Chemical reaction 1: 4Cu + O₂ → 2Cu₂O.
n(Cu) = 88,8 ÷ 63,55.
n(Cu) = 1,4.
n(O) = 11,2 ÷ 16.
n(O) = 0,7.
n(Cu) : n(O) = 1,4 : 0,7.
n(Cu) : n(O) = 2 : 1.
Compound is Cu₂O.
2) Chemical reaction 2: 2Cu + O₂ → 2CuO.
n(Cu) = 79,9 ÷ 63,55.
n(Cu) = 1,257.
n(O) = 20,1 ÷ 16.
n(O) = 1,257.
n(Cu) : n(O) = 1,257 : 1,257.
n(Cu) : n(O) = 1 : 1.
Compound is CuO.
A. This is not a redox reaction. It is an example of combustion.
<h3>Combustion reaction of hydrocarbon</h3>
During the combustion of a hydrocarbon, the hydrocarbon reacts with oxygen to create carbon dioxide, water, and heat.
<h3>Example of combustion reaction</h3>
2C8H18 + 25O2 → 16CO2 + 18H2O
Thus, we can conclude that, this is not a redox reaction. It is an example of combustion.
Learn more about combustion here: brainly.com/question/9425444
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Answer:
gain or loses electrons.
Explanation:
Because the atom need to be balanced.
