Tetraamminecopper(II) sulphate hydrate Write-up Essay Example for Free

Tetraamminecopper(II) sulphate hydrate Write-up Essay Purpose The purpose of this experiment is to form tetraamminecopper(II) sulphate hydrate and determine the yield. Materials CuSo4à ¯Ã‚ ¿Ã‚ ½5H2O NH3 (concentrated) Ethanol 50 cm3 measuring cylinder 250 cm3 beaker Spatula Equipment for vacuum filtration Procedure Weigh out approximately 5.0g of CuSo4à ¯Ã‚ ¿Ã‚ ½5H2O Dissolve it in 30 cm3 water in the beaker Add 10 cm3 concentrated ammonia (NH3) and stir the solution Add 40 cm3 ethanol and stir carefully for a couple of minutes. Filter the solution through equipment for vacuum filtration. Transfer the product to a clean weighing boat and leave to dry. Procedure and observations in class First 5.01g of CuSo4à ¯Ã‚ ¿Ã‚ ½5H2O was weighed out. After it was dissolved in 30 cm3 water, in the beaker, the solution got the colour blue. Next was 10 cm3 concentrated ammonia (NH3), which was added into the solution and the colour dark blue was observed. Then 40 cm3 ethanol was added and the solution got the colour bright blue. Then the solution was filtered through a Buchner flask and the final product was weighed in a plastic weighing boat. The total mass was 5.98g, from which the weight of the boat, 1.16g, has to be subtracted. So the mass of the final product was 5.98 1.16 = 4.82g. Data processing 1. Calculate the number of moles CuSo4à ¯Ã‚ ¿Ã‚ ½5H2O used. To find out the number of moles the formula n = m / Mr has to be used. Mr = 64 + 32 + (16 x 4) + (5 x 16) = 250 m = 5.01 n = 5.01 / 250 = 0.02004 à ¯Ã‚ ¿Ã‚ ½ 0.0200 moles (3 s.f.) 2. Concentrated ammonia contains 25% NH3 by mass. The density of concentrated ammonia is 0.91g/cm3 . Calculate the number of moles of NH3 . Density of con. ammonia = 0.91g/cm3 and in the procedure there was used 10 cm3, so therefore mass of ammonia used: 0.91 x 10 = 9.1g Since only 25% of ammonia is NH3 , mass of NH3 : 9.1 x 0.25 = 2.275g From here the amount of moles can be calculated by the formula n = m / Mr. Mr = 14 + (1 x 3) = 17 m = 2.275g n = 2.275 / 17 = 0.134 moles (3 s.f.) 3. Which of the reactants is in excess? Which is the limiting reagent? CuSo4à ¯Ã‚ ¿Ã‚ ½5H2O NH3 Number of moles (n) 0.02 0.134 Divide by smallest ratio 0.02 / 0.02 = 1 0.134 / 0.02 = 6.7 Divide by stoichiometric co-efficient from equation (Equation below this table) 1 / 1 = 1 6.7 / 4 = 1.675 Reactant in excess or limiting reagent Limiting reagent Reactant in excess (1)CuSO4 . 5H2O + 4NH3 Cu(NH3)4SO4 . H2O + 4H2O 4. Calculate the theoretical yield of Cu(NH3)4SO4 . H2O From the equation above it can be seen that the ratio between CuSO4 . 5H2O and Cu(NH3)4SO4 . H2O is 1 : 1. Therefore 0.02 moles of CuSO4 . 5H2O will give 0.02 moles of Cu(NH3)4SO4 . H2O. By using the formula m = Mr x n the theoretical yield can be calculated: n = 0.02 Mr = 246 m = 0.02 x 246 = 4.92 g Calculate the yield in percentage of the theoretical and comment on any difference. The yield in percentage can be calculated by the formula: actual mass / expected mass. 4.82 / 4.92 à ¯Ã‚ ¿Ã‚ ½ 97.9% (3 s.f) Because the difference is so small (2.1%) the experiment can be considered successful. The difference could have been caused by different things like: a small measurement mistake, a little bit was spilt or not transferred when the solution was held in the Buchner flask.

A Comparison And Contrast Of The Supernaturals Active Role In The Liv :: essays research papers

A Comparison and Contrast of the Supernatural's Active Role in the Lives of Mary Rowlandson and Benjamin Franklin The literature written during this time period reflects the important part the supernatural (God) played during those changing times. The new world was struggling for a new identity. Were these individuals also defining the role of God to themselves? In the preceding discussion the lives of Mary Rowlandson and Benjamin Franklin will be discussed. Each wrote a narrative of their life experiences. There are marked contrasts and comparisons between these two individuals related to their perceptions of God. Religion was a vital part of life in colonial America. A shift from theism to deism was occurring. The Puritans of this time were fleeing the Church of England. Their hope was to return to the more primitive ways, to reject the churches hierarchy and ritual. Mary Rowlandson, a puritan in Lancaster, Massachusetts was captured by Indians, along with three of her children in the year 1676. In her narrative she relates the story of her survival in the wilderness for a period of three months. She is taken away from her home and husband, "all was gone (except my life); and I knew not but the next moment that might go too" (127). Benjamin Franklin's The Autobiography is an account of his life and begins with his boyhood life in Boston. He later flees to Philadelphia to escape his brother's rule over him. He relates how he was "dirty", "fatigu'd", and "Want of Rest" (222). In these depictions we can see an analogy. These individuals are removed from their homes and families. Although Benjamin Franklin's removal was of his own free will. They each suffered as they no longer had the comforts of which they were accustomed. Rowlandson's faith was remarkable considering all that she endured. Through out the narrative she must rely on her faith in God. She incorporates numerous verses from the Bible to offer explanations for all that she has suffered, "Wait on the Lord: be of good courage, and he shall strengthen thine heart: wait, I say on the Lord" (129). It is also noted that she was able to use her trade to survive, "knitting a pair of white cotton stockings for my mistress"(130). This is also a parallel to Franklin in that he also used his trade to survive. But one must ask what is motivating Rowlandson? Is she writing for posterity or is she merely egocentric? Rowlandson has depicted herself as the ultimate Puritan. Was the glory to God or to herself? She also relates here "how many Sabbaths I had lost and misspent" (128).

Jack and Jill Twisted Story Essay

The sun was setting in Ville ville, and Jack and Jill were off to a party. They were so pumped for this party; they decided to go to the Hill hill to get some magic moon water to drink at the party. The hill was not very steep, it was very humble, but the problems isn’t with the hill it is with the magic moon water, if taken at the right time, you will be cursed and turn into specks of dust. The water they got made them the best partiers on the planet, and the water that they were to drink was to make them the best partiers for eternity. The water was in many puddles in around the hill, if the water forms and the moon perfectly pass over it while you take it you’re safe. So as the stride up the hill as the day became night, it was about 7:00pm and the party wasn’t ‘till 11:00pm. They were starting to get worried that they might not make it to the party. While they were going up the hill, Jack staggered down the hill and broke his crown. Now they’re going to miss the magic moon water time and the party. Jack had tripped over a rock that maybe formed the people who failed to take the water on time and turned into specks of dust. Jill came rushing to see what was wrong, but she told him that he was being pathetic and that they were going to buy him a new crown from the costume shop on their way to the party. Jack ended up falling into one of the magic moon water puddles, so Jill had to pull him out of there before he turned into specks of dust. While Jill tried to pull him out, she struggled, because she’s trying to pull out a 125 pound guy who was stuck in a hole. Then later after a long time of Jill trying as much as she could to pull him out, the moon passed over and Jack was slowly turning into a small speck of dust, and Jill was standing there betwixt and unsure about what to do to help him. Jill collapsed to the ground and was trying not to roll down the hill, but she slipped on some water, and then started to roll down the hill stopping at the bottom of the hill crippled because the impact of the crash had crushed all the bones in her body, and she died a slow and painful death from all the internal bleeding and the pain.

Seesaw Candle Fire Magic Trick

The seesaw candle magic trick is a fire science trick that teaches how combustion and Newtons Third Law of Motion work. A candle, balanced between a pair of glasses, rocks or seesaws up and down on its own. The motion continues as long as the candle continues to burn. If one side of the candle starts out heavier than the other, the motion of the candle will act to equalize the mass on either side of the pivot point. Its a simple trick, but eye-catching and interesting! Seesaw Candle Trick Materials Long candleNeedle2 glasses or jars that are the same height Long, thin candles work best for this trick. You can even use a pair of candles that are connected to each other. Procedure The first step is to expose wick at both ends of the candle so take a look at the bottom of the candle. If it has some wick pressed onto the bottom of the wax, loosen it so that you will be able to light it. On the other hand, if there isnt any wick at the bottom of the candle, use a knife to cut away enough of the candle to expose wick. You dont need a particularly sharp knife. In fact, its better to use a dull knife so that you dont accidentally cut the wick.Push the needle through the candle about halfway down its length. You dont have to be exact, but if you arent very good at gauging halfway points, then use a ruler to measure your candle, divide that number by two and push the needle through the candle at that point. If the candle wax is soft, you may be able to push the needle through the candle with minimal effort, but if the wax is hard or your candle is thick, then grasp the needle with pliers or tweezers, heat it in a flame and push it through the candle. The hot needle sh ould pass through the wax fairly easily. The trick still works if you accidentally bend the needle.Balance the needle and candle between a pair of glasses. It is okay if one end of the candle is heavier than the other.Light both ends of the candle. The candle will rock up and down, like a seesaw. You can watch a video of the project if youd like to see what to expect. How It Works The candle moves in response to forces acting on it, trying to reach equilibrium. The combustion reaction turns the candle wax into carbon dioxide gas and water vapor, making the burning end of a candle lighter. If one side of the candle burns more quickly than the other, the lighter side of the candle moves up. The lower side of the candle is angled such that the flame melts the wax, causing it to drip down. This not only lessens the mass at that end of the candle, but the force from the dripping wax actually pushes the end of the candle up! This is Newtons Third Law of Motion, which states that for every action, there is an equal and opposite reaction. More Fire and Candle Science Magic Traveling Flame Candle Magic TrickBlow Out a Candle with Chemical MagicTrick Birthday CandlesEdible Candle Trick Tips and Safety This is a fire project, so use adult supervision and avoid trying this trick near curtains, pets, gasoline... you get the picture.​Lighter candles respond more dramatically to changes in mass than heavier ones. Ergo, lighter candles will give you a better range of motion than heavier candles. If you use a very big candle, you wont see much motion at all. When in doubt, lighten up! Disclaimer: Please be advised that the content provided by our website is for EDUCATIONAL PURPOSES ONLY. Fireworks and the chemicals contained within them are dangerous and should always be handled with care and used with common sense. By using this website you acknowledge that ThoughtCo., its parent About, Inc. (a/k/a Dotdash), and IAC/InterActive Corp. shall have no liability for any damages, injuries, or other legal matters caused by your use of fireworks or the knowledge or application of the information on this website. The providers of this content specifically do not condone using fireworks for disruptive, unsafe, illegal, or destructive purposes. You are responsible for following all applicable laws before using or applying the information provided on this website.