An 8th grade goes to a restaurant for dinner with their family. At dinner, the student orders iced tea. The ice and tea combined to weigh 210 grams. The student then added sugar and lemon to their tea. The sugar weighed 20 grams and the lemon weighed 15 grams. After adding the sugar and lemon, the student stated the tea weighs 225 (210 grams ice & tea + 15 grams lemon) grams since only the lemon would add weight to the tea because the sugar was dissolved. Do you agree or disagree with the statement? Justify your choice.

Disagree, the total mass is 245 grams.

Explanation:

We need to keep in mind the Law of Conservation of Mass. Each gram added to the lemonade (a system) will remain there unless it is somehow removed. The added mass of both sugar and lemon count for the total mass (210+20+15), even if the sugar was dissolved.

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).