Answer: The correct option is ALL OF THE ABOVE.
Explanation:
TITRATION is a type of volumetric analysis which is used for determining the concentration of solutions. In this process a specific volume of a solution is placed in a conical flask by means of a pipette and small quantities of a second solution is slowly added from a burette until the end point is reached. This is determined by a means of an indicator which shows a characteristic colour change.
During titration, the following precautions should be followed to avoid errors and maintain standardisation in the experiment.
--> Any air bubble in the burette and pipette must be removed during measurement
--> the burette tap should be tightened to avoid leakage.
--> Remove the funnel from the burette before taking any reading to avoid errors in reading the volume.
--> use the base solution such as Sodium Hydroxide Solution to rinse the burette after washing with soap and tap water:
• to remove any air bubble and fill it's tip
• to remove any residual liquid from the water and soap solution which may interfere with the results of the experiment.
• to check if the burette is in good condition.
Therefore all of the above options to the question are correct.
<span>The problem has to do with oxidation states of the matter. The oxidation state of oxygen will always be -2 with the exception of peroxides which will have a state of -1. The overall balanced state of chemical compounds will be 0, so the oxidation state of Mn in MnO2 will be +4. The oxidation state of MnO4- will then be +7 to balance out to the negative one charge. The state change from +4 to +7 is 3, thus three electrons have to be lost in order for this to happen; a loss of a charge of -3 results in an increase of charge of 3. Oxidation is always the process of 'losing' electrons.
</span><span>E] MnO2(s) MnO4-(aq</span>
Answer:
See explaination
Explanation:
Please kindly check attachment for the step by step solution of the given problem.
When reversing a given reaction, we simply change the sign of the standard enthalpy change value. Therefore, the reaction will become:
H₂O → H₂ + 0.5O₂, ΔH = 286kJ
This is because if a certain amount of energy is released when a reaction occurs, the same amount of energy must be supplied for the reaction to occur in the reverse direction.