Answer:
Always be scared of electroplating. ...
Follow all electrical safety precautions. ...
Use all safety Precautions. ...
Use that Fume Hood. ...
It's a chemistry lab, set it up like one. ...
Always add acid to water. ...
Don't overheat your solutions! ...
Don't mix acid and cyanide solutions.
The speed of a longitudinal wave would increase, as the kinetic energy molecules would move quicker in response to the higher temperature.
I think this is how you do it:
Answer: 3
Explanation:
An oxide-reduction reaction or, simply, redox reaction, is a <u>chemical reaction in which one or more electrons are transferred between the reactants</u>, causing a change in their oxidation states, which is the hypothetical electric charge that the atom would have if all its links with different elements were 100% ionic.
For there to be a reduction-oxidation reaction, in the system there must be an element that yields electrons and another that accepts them:
-
The oxidizing agent picks up electrons and remains with a state of oxidation inferior to that which it had, that is, it is reduced.
- The reducing agent supplies electrons from its chemical structure to the medium, increasing its oxidation state, ie, being oxidized.
To balance a redox equation you must <u>identify the elements that are oxidized and reduced and the amount of electrons that they release or capture, respectively.
</u>
In the reaction that arises in the question the silver (Ag) is reduced <u>because it decreases its oxidation state from +1 to 0</u> and the aluminum (Al) is oxidized because <u>its oxidation state increases from 0 to +3</u>, releasing 3 electrons (e⁻). Then we can raise two half-reactions:
Ag⁺ + e⁻ → Ag⁰
Al⁰ → Al⁺³ + 3e⁻
In order to obtain the balanced equation, we must multiply the first half-reaction by 3 so that, when both half-reactions are added, the electrons are canceled. In this way:
(Ag⁺ + e⁻ → Ag⁰ ) x3
Al⁰ → Al⁺³ + 3e⁻ +
-------------------------------------
3Ag⁺ + Al⁰ → 3Ag⁰ + Al⁺³
So, the coefficient of silver in the final balanced equation is 3.
<u>Answer: </u>The correct answer is 1.32 mol 
<u>Explanation:</u>
For the reaction of lithium and hydrofluoric acid, the equation follows:
By Stoichiometry of the reaction:
if 2 moles of lithium is producing 1 mole of hydrogen gas,
Then, 3.50 moles of lithium will produce = 
of hydrogen gas.
- Now, to know the theoretical yield of hydrogen gas, we use the equation:
...(1)
Moles of hydrogen gas = 1.75 mol
Molar mass of hydrogen gas = 2 g/mol
Putting values in above equation, we get:
- To calculate the percentage yield, we use the equation:
Percentage yield = 75.5 %
Theoretical yield = 3.5 g
Putting values in above equation, we get:
- Now, calculating the moles of hydrogen gas, we put the value in equation 1, we get:
Hence, the correct answer is 1.32 mol
