Answer:
B) is reduced.
Explanation:
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Consider the following reactions.
4KI + 2CuCl₂ → 2CuI + I₂ + 4KCl
the oxidation state of copper is changed from +2 to +1 so copper get reduced and it is oxidizing agent.
CO + H₂O → CO₂ + H₂
the oxidation state of carbon is +2 on reactant side and on product side it becomes +4 so carbon get oxidized and it is reducing gent.
Oxidizing agents:
Oxidizing agents oxidize the other elements and itself gets reduced.
Reducing agents:
Reducing agents reduced the other element are it self gets oxidized.
I think you means the KO2 reacts with H2O. The equation of this reaction is 4KO2+2H2O->4KOH +3O2. The ratio of mole number of O2 and KO2 is 3:4. So the mole number of O2 produced is 0.500/4*3=0.375 mol.
The simplest level at which life may exist is a cell
Answer: 90.04°C
Explanation: <u>Calorimeter</u> is a device measures the amount of heat of a chemical or physical process. An ideal calorimeter is one that is well-insulated, i.e., prevent the transfer of heat between the calorimeter and its surroundings. So, the net heat change inside the calorimeter is zero:

Rearraging, it can be written as

showing that the heat gained by Substance 1 is equal to the energy lost by Substance 2.
In our case, water is gaining heat, because its temperature has risen and so, brass is losing energy:

Calculating:
![m_{w}.c_{w}.\Delta T=-[m_{b}.c_{b}.\Delta T]](https://tex.z-dn.net/?f=m_%7Bw%7D.c_%7Bw%7D.%5CDelta%20T%3D-%5Bm_%7Bb%7D.c_%7Bb%7D.%5CDelta%20T%5D)
![100.4.18.(18.4-15)=-[52.9.0.375.(18.4-T)]](https://tex.z-dn.net/?f=100.4.18.%2818.4-15%29%3D-%5B52.9.0.375.%2818.4-T%29%5D)
Note: final temperature is the same as the substances are in thermal equilibrium.
Solving:
418(3.4)= - 365.01 + 19.8375T
19.8375T = 1786.21
T = 90.04
The initial temperature for the sample of brass was 90.04°.
Answer:
12.89 moles
Explanation:
Before we solve the question, we have to balance the equation of the reaction first. The balanced reaction will be:
2 NO + 2 H2→ N2 + 2 H2O
There are 180.5g of N2 produced, the number of produced in moles will be: 180.5g / (28g/mol)= 6.446 moles
The coefficient of H2 is two and the coefficient of N2 is one. Mean that we need two moles of H2 for every one mole of N2 produced. The number of H2 reacted will be: 2/1 * 6.446 moles = 12.89 moles