In this experiment, the mass of copper and zinc is needed in order to receive its percent composition. To start off the experiment, the penny is from 1982 since the article was based off the 1982 pennies. The penny’s mass is weighed before the copper is scraped off the surface. By taking the mass beforehand, the total mass of the penny is used in the percent composition calculation. Also, scraping off the bits of the copper will expose the zinc to the hydrochloric acid since the zinc will react to the acid. The penny and the acid will be left in a beaker overnight to give the reactants more time to react. The reactants will form into aqueous, leaving only copper as a solid in the acid because the copper won’t react with the hydrochloric acid …show more content…
Before the penny is weighed, there is still acid on the penny, so in order to get the actual copper mass, the penny has to be washed. When getting the penny out of the beaker, the solution must be diluted because the acid can not be physically touched. Now, the penny has to be dried by a bunsen burner to ensure water molecules won’t be part of the weight of copper. The penny will lightly touch the fire, and once the whole penny is dried, the penny is weighted to get the mass of copper. The mass of copper is subtracted from the total mass of the penny to get the mass of zinc. Now the weight of copper and zinc is collected, the percent composition can be
The unknown bacterium that was handed out by the professor labeled “E19” was an irregular and raised shaped bacteria with a smooth texture and it had a white creamy color. The slant growth pattern was filiform and there was a turbid growth in the broth. After all the tests were complete and the results were compared the unknown bacterium was defined as Shigella sonnei. The results that narrowed it down the most were the gram stain, the lactose fermentation test, the citrate utilization test and the indole test. The results for each of the tests performed are listed in Table 1.1 below.
The mixture was poured through a weight filter paper and Sucrose washed with a 5ml of dichloromethane. The resulting solid was left in a breaker to dry for one week, to be measured. Left it in the drawer to dry out for a week and weighted it to find the sucrose amount recovered amount.
My goal in this experiment was to determine the amount of zinc (in grams) on 5 different galvanized nails to see if this specific box was up to standard, as well as how consistent the weight of the zinc is on each nail and do so by measuring the weight of the nail initially, then take the zinc off with the hydrochloric
In 2001, United Sates Representative Jim Kolbe proposed a legislation to Congress to dispose the penny coin from the currency of America because of its small impact. Although his legislation failed, most people currently argue about the penny’s existence today. Even though the penny stood as a mark of history, it is useless and should be eliminated from America’s currency.
One of the best methods for determining mass in chemistry is gravimetric analysis (Lab Handout). It is essentially using the the mass of the product to figure out the original mass that we are looking for. Thus the purpose of our experiment was to compare the final mass in our reaction to the initial mass and determine the change in mass.
The purpose of this lab was to calculate the percent composition by mass of oxygen in potassium chlorate.
The purpose of this lab was to study the response of the genus Daphnia to chemical stimuli and to examine human responses to different stimuli. A stimulus is an incentive; it is the cause of a physical response. Stimuli can have a physical or chemical change; an example of a physical change is a change in temperature and sound. An example of chemical change would be changes in hormone levels and pH levels. Muscular activity or glandular secretions are responses that occurs when stimulus information effects the nervous and/or hormone system. Daphnia is a genus; it is a small crustacean that lives in fresh water. The body of the daphnia is visible and its internal organs are clearly seen thus it was chosen for this exercise. The
The experiment we did was Copper Cycle. We reverted the copper to its elemental form after a chain of reactions. We performed a series of reactions, starting with copper metal and nitric acid to form copper (ii) nitrate. Then we reacted copper with sodium hydroxide, sulfuric acid, nitric acid and zinc to form precipitates. In conclusion our percent recovery was 40.38%.
The experiment required our group to find out the mass and thickness of a single penny from a group of pennies, with each group of pennies’ being from different years. Tools such as calipers and eight scales were used to find the average mass and thickness of a single penny from each year. Our general hypotheses before conducting the experiment was that both the mass and the thickness of pennies would go down with each newer year of pennies.
Measure the mass using a triple beam balance or other scale to the nearest tenth of a gram
Planaria are one of many free-living flat worms that can be found in marine, aquatic, and terrestrial environments. Certain characteristics of planaria worms include an acoelomate body, a gut with no anus, lack of a blood vascular system, and a simple nervous system. The main reason as to why planaria are subjected to many studies is because of their unique ability to regenerate. Regeneration is the ability to re-grow lost body parts that may have been cut off. This is possible because the organism has the ability to form a blastema, which is an accumulation of undifferentiated cells, at the site of the wound. Regeneration is capable of occurring at various degrees throughout the animal kingdom. This unique process would never be able to be seen in human beings. Humans and other mammals
Being the first currency in the United States, dating back to 1787, the penny has been the longest serving currency - thanks to Abe Lincoln. In recent times, the penny has become a useless piece of material due to how costly everything is, the time consumed in making change, and the true objective to facilitate transactions. This is why the penny should be abolished from our society.
In the analysis, the hypothesis was that pennies made before 1982 were made out of a different substance than the pennies made after 1982. The hypothesis turned out to be true. The pre 1982 pennies were made out of copper which has a density of 8.6 g/mL and the post 1982 pennies are made out of zinc which has a density of 7.14 g/mL. So it can concur that mass for pennies made before 1982 are higher than pennies made after 1982. Some errors were when calculating. The densities for the pennies and making the graphs. When making the graphs, it can be suspected that each graph is wrong could be wrong due to not adding enough data points or misplaced points. For the data tables , it can also be suspected that the density for each data table could
Found the mass of a cylinder of Copper and the mass of a cylinder of Zinc on an electric scale, recorded
First of all, we will talk about what uses we have for the penny. The penny is a U.S. symbol in a way, so there is a comfort with keeping the penny. Most people in this country believe it is a useful coin, presents Joseph Carroll. In fact, most Americans are more likely to pick up a penny off the ground if they find one, rather than leave it (Carroll). By some calculations, rounding sales tax to the nearest penny rather than the nearest nickel (every cent rather than every five cents) saves Americans $1-2 billion per year