A mixture of Cu2 and CuO of mass 8.828g is reduced to copper metal with hydrogen:
Cu2O + H2 --> 2Cu + H2O
CuO + H2 --> Cu + H2O
If the mass of pure copper isolated was 7.214g, determine the percent by mass of CuO in the original sample
Let x = grams of CuO in the original sample.
y = grams of Cu2O in the original sample.
Eq. #1 x + y = 8.828 grams
Molar mass of CuO = 63.5 + 16 = 79.5 grams
Moles of CuO = x ÷ 79.5
Molar mass of Cu2O = 63.546 + 32 = 95.5 grams
Moles of Cu2O = y ÷ 95.5
According to the 2nd balanced equation, CuO + H2 --> Cu + H2O ,
1 mole of CuO produces 1 mole of Cu.
So, x ÷ 79.5 moles of CuO will produce x ÷ 79.5 moles of Cu
According to the 1st balanced equation, Cu2O + H2 --> 2Cu + H2O,
1 mole of Cu2O produces 2 moles of Cu
So, (y ÷ 95.5) moles of Cu2O will produce 2 * (y ÷ 95.5) moles of Cu
Since, the mass of pure copper isolated was 7.214 grams
Moles of Cu = (7.214 ÷ 63.5)
Moles of Cu from Cu2O + moles of Cu from CuO = total moles of Cu!!
2 * (y ÷ 95.5) + (x ÷ 79.5) = (7.214 ÷ 63.5)
Multiply by both sides by 95.5 * 79.5 * 63.5 to get rid of denominators
(2 * 79.5 * 63.5) y + (95.5 * 63.5) x = (7.214 * 95.5 * 79.5)
10,096.5 y + 6,064.25 x = 36,418.0755
Divide both sides by 6,064.25
x + 1.665 y = 6
Eq.#2 x = 6 – 1.665 y
Eq. #1 x + y = 8.828
x = 8.828 – y
8.828 – y = 6 – 1.665 y
0.665 y = 2.828
y = 4.25 grams of Cu2O
x = 8.828 – 4.25 = 4.58 grams of CuO
% CuO = (4.58 ÷ 8.828) * 100 = 51.88% CuO
The energy of a nuclear reactor gets converted to electricity by using steam. As steam converts mechanical energy to electricity.
Answer: Option C
<u>Explanation:
</u>
Nuclear reaction works on the principle of nuclear fission. The main functioning of nuclear reactor is the generation of neutrons by fission of Uranium oxide.
The rate of generation of neutrons need to be controlled in the reaction to have a controlled chain reaction which is suitable for generating electricity.
So, the controlling of rate of nuclear generation is done by moderators. The moderators are generally water or graphite in any nuclear reactor. So during these process, steam is produced in the reactor core which then flows through a turbine engine.
The steam rotates the turbines in the generator and thus the mechanical energy of the turbine during rotation is converted as the electrical energy in the generator.
Answer: The aluminium trihalide assists in the heterolytic bond fission of the bromine molecule.
Explanation:
The electrophilic aromatic bromination of acetalinide with molecular bromine requires the formation of Br+. This specie is formed when an Aluminum trihalide reacts with bromine. The Br-Br bond breaks heterolytically such that charged species are produced. This Br+ participates in the electrophilic aromatic substitution and AlX4- is formed where X4 shows a tetrahalide complex of aluminium