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What else can I help you with?
Characteristics of a good sample?
1. the sample should be representative thus carefully selected. 2. the sample should be adequate thus significant enough.
Sample A weighed 3 ounces Sample B weighed 814 thousandths of an ounce more than Sample A What decimal should you use to record the weight of Sample B?
.00814
Will margins of error for sample of size 80 be larger or smaller than those for sample size of 40?
They should be smaller for the sample size 80.
What happens to the crtitical value for a chi square test if the size of the sample is increased?
The size of the sample should not affect the critical value.
What should you take into considersation when selecting a sample for study?
When selecting a sample for a study, consider the target population to ensure it accurately represents the characteristics you want to investigate. Additionally, think about the sample size, as a larger sample can improve the reliability and validity of the results. It's also essential to consider sampling methods (random, stratified, etc.) to minimize bias and ensure that the sample reflects the diversity of the population. Lastly, ethical considerations, such as informed consent and confidentiality, should be taken into account.
Why should the endpoint be taken as the faint pink color of the indicator?
When using an indicator in a titration, the color changes happen when the titrant has reacted with all the substance of interest in the sample. As soon as the titrant isn't reacting with the sample any more, it starts reacting with the indicator, and continuing past the first hint of color will be using too much titrant, and the calculations for the concentration of the sample will be wrong. Phenolphthalein starts out pink, but will turn red as the pH keeps changing as you go further past the endpoint of the titration.
When should back titration be used instead of direct titration?
Back titration is often used when the analyte reacts slowly with the titrant or when interfering substances are present in the sample that can interfere with the direct titration process. Additionally, back titration can be more accurate when dealing with weak acids or bases where the endpoint may not be easily detected.
When do you know endpoint of titration?
The endpoint of a titration is reached when the indicator changes color, signaling that the stoichiometric equivalence point has been reached. This is the point at which the moles of titrant added are chemically equivalent to the moles of analyte in the sample being titrated. It indicates the completion of the reaction and helps determine the concentration of the analyte.
Conclusion for the determination of iron by permanganate?
The conclusion for the determination of iron by permanganate is that oxidation of iron is one of the most popular titrations. All permanganate titrations, when used as a titrant, should use different techniques to read volume of liquid in the burette.
Where should the titrant be placed at the beginning of the experiment?
The titrant should be placed in the burette at the beginning of the experiment.
What are the precaution steps in during titration?
Ensure that all glassware and equipment are clean and dry before starting the titration. Use a calibrated burette to accurately measure and deliver the titrant into the analyte solution. Perform a rough titration to determine an approximate endpoint before carrying out the actual titration. Record the volume of titrant added at the endpoint accurately to calculate the concentration of the analyte.
List four requirements of an ideal titration?
The reaction should be stoichiometric. The reaction should be rapid. The reaction should be specific with no side reactions or interference from other substances. The reaction must be quantitative.
Requirements for precipitation titration?
Precipitation titration requires a soluble reactant that forms a precipitate upon reaction with the analyte, a suitable indicator to detect the endpoint of the titration, a method to control the addition of the titrant, and conditions under which the analyte and titrant concentrations are stoichiometric. Good stirring and controlled temperature may also be necessary for accurate results.
When should back titration used instead of back titration?
when we do not know nothing about the other titrant.
When performing titrations why should you constantly stir the contents?
During a titration, reactant from the burette are added drop wise. It may not reach the bottom, which might result in an incorrect endpoint. The flask is always stirred to mix the reactants in the flask evenly.
How much time should be allowed for the titrant to drain from the buret wall before a reading is made?
About 30 seconds is typically sufficient to allow the titrant to drain from the buret wall before taking a reading. This ensures that all the titrant has been delivered into the solution being titrated and minimizes errors in the titration results.
Why should you not wash and blot the pH meter during titrations?
Washing and blotting the pH meter during titrations can introduce errors in the measurements by changing the electrode potential or diluting the sample being measured. It is recommended to rinse the electrode with the titrant solution instead to maintain accuracy in the titration process.
