Answer:
Correct answer is Li
Explanation:
Lithium reacts with chlorine to form Lithium chloride.

This is a redox (Oxidation -Reduction) reaction

Hence the reducing agent in this reaction is Li
Answer:
CH4 + 2 O2 --> CO2 + 2 H2O
Explanation:
CH4 + 2 O2 --> CO2 + 2 H2O is the only reaction where an element (oxygen) undergoes a change in oxidation state. In this reaction oxygen changes disproportionately to O⁻². That is ...
O₂ → CO₂ + 4e⁻ ==> oxidation
<u>O₂ + 4e⁻ → H₂O ==> reduction </u>
2O₂ + 4e⁻ → CO₂ + H₂O + 4e⁻ ==> Net oxidation-reduction
=> 4e⁻ gained by one mole O₂ in formation of CO₂ = 4e⁻ lost by the other mole O₂ in forming H₂O.
Then...
Including CH₄ (whose elements do not undergo changes in oxidation states) requires doubling reaction to balance by mass thus giving ...
2CH₄ + 2O₂ + 8e⁻ → 2CO₂ + 2H₂O + 8e⁻
Cancelling 8 reduction electrons on left with 8 oxidation electrons on right gives...
2CH₄ + 2O₂ → 2CO₂ + 2H₂O
Answer:
0.3 moles of H2 will be produced.
Explanation:
Balanced reaction: 2 Al + 6 HCl → 2 AlCl3 + 3 H2
Given Al mass = 5.4 g, we know Mr of Al is 27
Using the formula:
moles = mass / Mr
moles of Al = 5.4 / 27
moles of Al = 0.2 moles
Here we see that "2" molar mass before Al; so in this reaction, "1" molar mass will have [(0.2)/2] = 0.1 moles. He see "3" molar mass before H2, therefore moles of H2 is (3 * 0.1) = 0.3 moles.
Dimensional analysis is a convenient technique to determine if the solution you're following would lead you to the answer that you're looking for. It is the manipulation of units. Like units are cancelled whenever they appear on the numerator and the denominator side. For example, if the speed is 5 m/s and the time is 2 s, the distance would be:
(m/s)*(s) = m
So, you would know that the solution would be 5*2 because it yields the unit for distance.
Hence, dimensional analysis could prevent crash by calculating the right velocities or distances of the two vessels to prevent collision.
Answer:
Just add a plenty of dots in the first one and very few dots in the second one