In Section A, the average mass of the 50 ml beaker was weighed 3 times using 2 different electronic balances. The final average mass recorded was 33.73g. The volume of distilled water needed was calculated from the mass of water using the density= 0.9971g/mL in Section B. The volume of water needed was transferred using pipette, graduated cylinder and Erlenmeyer flask respectively. In Section C, a pipette was calibrated by measuring the water temperature and the density was determined. The average mass of water was calculated and the reading was 20.68g. The value for the relative average deviation was 5.33%. In Section D, the crucible, crucible lid and anhydrous magnesium sulphate were weighed and the % water in magnesium sulphate hydrate was recorded calculated which is 41.56%. In …show more content…
The graph as circumference against the diameter of various beakers shows a straight line that increases linearly. The greater the size of beaker used, the greater the circumference and the diameter measured. In section F, CH3OH is placed in the category of toxic, flammable and reactive. NaOCH3 is under the group of toxic, flammable, reactive and corrosive. CH2O2 is corrosive which chemically damaging to living tissue. The boiling point of the water increases when NaCl is added to it but the ice point of water decreases when NaCl is added to it. Our result supports the hypothesis where the boiling point increases from 96 °C to 99.5 °C. However the result for the ice point increases when NaCl is added. In this experiment, the accuracy using various of volumetric glassware pieces and the proper usage of basic laboratory equipment were determined. In addition, the correct way to analyse data for lab findings was learnt. The precise details of the experiment were presented to help other researches to further their findings in this
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Background Information In this lab KCl, NaCl, and a mixture of MgCl2 and NaCl are the independent variables that all lower the freezing point of water. Ice is used as the controlled variable because it is what the salts are lowering the freezing point of. Salt (Na) weakens intermolecular forces of water, thus lowering the the freezing point. This is why in colder climates where icy roads and walkways are a liability, salt is often scattered over areas that are slick with frozen water.
Characteristic Property- Test 3- Flame Test Materials: tongs, unknown 6, matches Procedure: at the sink, we held a small piece of towel that was soaked with the liquid fraction 6 and held it with the tongs for the lit match to light it on fire. Data: We found that the unknown is flammable after it automatically lit on fire and burned during the burn test.
In the next steps the density of water between 30-40 °C, 40-50 °C and 50-60 °C was measured. Then our results ρ vs T and also density vs temperature values given in the Steam Tables were plotted on the same graph in order to compare. In the second part the density of water was measured by density bottle. The densities obtained from the experiment are 995, 992.5, 991, 990 kg/m3 for the first part and
Using the thermometer, the temperature was measured and recorded. Then, the 25-mL graduated cylinder was filled with 25 mL of distilled water, and its mass was measured and recorded. The density of the water was found using the temperature and the Density of water index. Moreover, the calculated volume of water was calculated using the formula of density, and the difference between observed volume and calculated volume was found. This process was then repeated using the 50-mL beaker and the results were recorded.
With following the procedure, the experiment was completed very easily. The technique used worked very well. The graduated cylinder were dried after each trial to ensure each water level was equal. The air bubble were risen to the top to ensure the equal amount was measured. Systematic errors can not be eliminated by averaging In principle, they can always be eliminated by changing the way in which the experiment was done.
The least reliable test result was “Part D” the heat of solution of salt “579” which was significantly different from potassium chlorides heat of solution. The heat solution of salt “579” was -2.44 kcal/mol and the heat solution of potassium chloride is 4.404
Procedures 1.First thing needed is a plastic bag open the plastic bag and take about a teaspoon of calcium chloride, put the calcium chloride in one corner of the bag. Then take about a half teaspoon of sodium bicarbonate and put it in the opposite corner of the bag. Then lay the bag flat on the table use about 5 mL of phenol red. Once the phenol red is in quickly lift your bag and put all the substances in one corner. Then observe 2.Reference procedure one for first step.
The decomposition of NaHCO3 is an example of Prevention within Green Chemistry principles because all solid waste in this experiment is collected and used again. The only gaseous wastes generated by the reaction in the experiment are carbon dioxide and water, which are benign (Lab 3). The decomposition reaction of NaHCO3, generates virtually no waste, therefore less hazardous chemical syntheses. The byproducts of the reaction are gaseous CO2 and H2O which possess little or no toxicity to human health and the environment, because of the amounts released in this experiment. (Lab 3).
Procedure Activity 1: Fill 6 large beaker halfway with distilled water, making sure all beakers have equal amounts of water. Cut 6 30 cm dialysis bags and label each bag with a letter, A through F. Fill each dialysis bag with 15 mL of solution A through F that corresponds with the lab on each bag. For example, bag A is filled with solution A. Measure the mass of each dialysis bag and record masses of each bag in BILL. Cover the beakers with paper towel and leave the bags in the beakers overnight. Remove the dialysis bags from the beakers and let dry.
Introduction: In this lab, of water in a hydrate, or a substance whose crystalline structure is bound to water molecules by weak bonds, is determined by heating up a small sample of it. By heating, the water of hydration, or bound water, is removed, leaving only what is called an anhydrous compound. Based on the percent water in the hydrate, it can be classified as one of three types: BaCl2O ⋅ 2H20, with a percent water of about 14.57%, CuSO4
There are many different ways of how trigonometry applies to the real world. For example, some occupations that use trigonometry on an everyday basis are astronauts, physicists, architects, surveyors, crime scene investigators, and engineers. In history, trigonometry can be traced all the way back to about 4,000 years ago. Another example of how we apply trigonometry on an everyday basis is technology and music. Sound navigates through waves and this style is still not as formal as a sine or cosine capacity, but it is effective in advancing computer music.
The first lesson that I taught in Mr. Robert Speicher’s Trigonometry/Pre-Calculus class involved a factoring technique called the “Rational Root Theorem”. I taught this lesson in conjunction with the Explicit Direct Model of Teaching. For the beginning of my set, I showed my students a video from YouTube called “The Exponent Rules Song” in order to activate their prior knowledge of exponents and to appeal to my students who were musicians. I then presented a graphic organizer on the white board that showed the four rules of exponents by calling on four random students who did not appear to be listening to the song to explain one of the rules of exponents.
Investigation of the effect of NaCl concentration on the evaporation rate of water. Chemistry HL Internal Assessment Vitaebella Tsang Ao Ling Contents page Contents page 2 Introduction 3 Design 4 Research question 4 Variables 4 Method 5 Results 6 Discussion 9 Evaluation 9 Bibliography 10 Introduction Many recipes call for salt to be added to the water when cooking pasta to add flavor, but there has been common belief or misunderstanding that adding salt will make the water boil faster. However, it is now known that that is not the fact, and that adding salt will do the opposite and make the water boil more slowly instead.
The temperature of the sulphuric acid was not measured throughout the experiment, however the room in which the experiment was conducted was kept constant, so the chance of any large error due to unknown temperature of the sulphuric acid was most likely reduced. The amount of sulphuric acid used was also controlled by measuring 100mL with a 100mL measuring cylinder to ensure that the results would be consistent. The volume of the agar cubes was calculated from the surface area of each agar cube, both before and after they had been in the sulphuric acid. This increased the reliability of the results as it allowed the rate of diffusion of the sulphuric acid into the agar cubes to be calculated more accurately. The concentration of the acid was 0.1M, which was placed in all three agar cubes to maintain consistency of results.