What is the role of an indicator in an acid-base titration? in your answer, identify how an appropriate indicator is chosen and use the terms "end point" and "equivalence point" to explain how an indicator works.

indicate the end point of a titration

Explanation:

The indicators are substances that being weak acids or bases to be added to the sample on which the analysis is desired, there is a chemical change that is noticeable, usually a color change; this occurs because these unionized substances have a different color than when ionize .

The color variation is called a turn for this the indicator must change its chemical structure either by losing or accepting a proton.

This change in the indicator occurs because during the analysis a change in the conditions of the sample takes place and indicates the end point of the assessment. The operation and the reason for this change vary greatly depending on the type of assessment and indicator

On the other hand,  the point of equivalence of a valuation (another word for titration) is called the point at which equivalent amounts of reactive solution and the substance to be determined have been mixed. For example, in the case of titration of a solution of hydrochloric acid with a solution of sodium hydroxide, the equivalence point is reached when exactly one mole of NaOH is added for each mole of HCl. In this case the acidity of the resulting solution will be equal to that of pure water. We can't see it, but we can see the final point thanks to the indicator.

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).

(b) which contains higher levels of vitamin b, oranges or spinach?

explanation:

you can eliminate a, c, and d because they are questions based on opinions.