A hot plate was placed under the ring stand. 50 mL of 3.0 M NaOH in a 250 mL beaker and a stir bar was placed in the beaker. The beaker with NaOH was placed on the hot plate and 3.75 grams of NaAlO2*5H2O was placed in the beaker. The temperature probe was placed in the beaker with the solution, not touching the bottom of the beaker. The solution was heated and stirred till the solution dissolved.
The scientists will conduct the experiment by taking four cups of water one that is just salt mixed with water, another that is just water, a third cup that is just ice water and finally a forth cup that is vinegar and water mixed. After that the scientists will drop one Alka-Seltzer tablet into each cup and see how long it takes for it to completely dissolve. The scientists will conduct these three times for
Claim: Through the tests performed in lab, it was concluded that unknown powder E was NaHCO₃, powder K was MgSO₄ and powder V was cornstarch. Evidence: Unknown element E was first tested with phenolphthalein and the solution turned pink, this test left 3 possible compounds; NaHCO₃, Na₂CO₃, and CaCO₃. Next the compound was tested with iodine and the solution turned yellow showing that now there was two compounds that could be the identity of unknown powder E; NaHCO₃ and CaCO₃. After that compound E was tested for being soluble in water, the powder was soluble, this proved that unknown element E is NaHCO₃. Unknown Element K was also first tested following the steps for the phenolphthalein test and the compound turned clear, this test ruled out NaHCO₃, Na₂CO₃, and CaCO₃. Second the unknown powder was tested with iodine and the solution turned yellow, leaving NaCl, CaSO₄ and MgSO₄ as possible identities of unknown powder K. Considering this it was next tested for solubility in H₂O, and it was concluded that the compound was soluble. Next the unknown element was tested with sodium hydroxide and a white precipitate formed proving that unknown powder K was MgSO₄ because NaCl and CaSO₄ were ruled out.
Vacuum filtration was performed on the crude product, then it was recrystallized for purification. Melting point analysis was conducted on the recrystallized product to determine its identity. 3. The three possible mechanisms in this experiment were syn-addition
The substitution reaction was successful but not fully effective. 19. If the data was inconclusive, then comparing various compounds and the unknown based on physical characteristics would be the first step, titrations would also be a good method. 20. To get a better yield, redoing the experiment would require careful attention in the recrystallization steps: amount of solvent used, how hot solvent is, if the mixture cools to room temperature before placing it in an ice
The purpose of this experiment was to see which solute, Splenda, granulated sugar, or salt, would dissolve the fastest in distilled water. Solutes can only dissolve in solvents when they are polar. A polar bond is a covalent bond that has two atoms where the electrons forming the bond are unequally distributed (About Education.com). This causes it have a dipole or separation of electrical charges moment making it polar. For example, in a water molecule the electrons are not shared equally because the oxygen has more of a charge than the hydrogen bonds making the hydrogens pull towards the oxygen.
The items that were massed were the evaporating dish, watch glass, and NaCO3. The materials were massed once before and once after being heated in the drying oven. The mass of the evaporating Dish before was 46.57 g; while after being heating was 60.15 g. The mass of the watch glass before was 57.97 g and after was 48.75g. There were two masses taken for the substance NaHCO3- one with the evaporating dish and one without, subtracted out after the lab was concluded. The mass of the substance with the dish was 48.79 g before and 62.33 g after; meanwhile, the mass of the substance without the dish was 2.22 g before and 2.18 g after. The mass of the NaHCO3 had changed after the reaction occurred along with after it was placed on the hot plate and being in the drying oven.
Calorimetry 1 The purpose of this experiment is to identify the mystery metal given to us (metal A). We are going to identify the mystery metal by looking at both its physical properties as well as its heat capacity. The heat capacity of the metal will be calculated using a setup/method described below. We will also look at the physical properties of the metal such as its magnetic properties, density, whether it is lustrous or dull, etc.
Introduction: The melting point of a pure substance is a characteristic that is physically consistent with each specific substance. When a substance is impure, it causes the melting point to decrease and the range of the melting point to increase. In order to identify a pure substance, it must be purified in order to get an accurate melting point estimation. Purification can be done through crystallization.
The two solvents in the unknown were correctly identified as acetone and toluene. The solvent with the lower boiling point was predicted to be acetone, as its boiling point was observed to be around 59 C, which was closest to the 56.5 C, the ideal boiling point of acetone. This result, however, had the possibility of being incorrect, since the boiling point of methanol, 64.7 C, was relatively close enough to the observed 59 C that methanol could have been incorrectly identified due to experimental errors such as turning the hot plate up too high. A similar situation could have occurred with toluene, the higher boiling point solvent, but this was less likely since there were no possible solvents that had a boiling point that close to toluene. The chromatogram confirmed the identity of the lower boiling point solvent as acetone, and the higher boiling point solvent as toluene.
Then, the boiling tubes were left in a water bath at 45°C. After 5minutes, the boiling tub, labelled A, was withdrawn from the water bath. 4) The sample was filtered using a Buchner funnel, collected in a sample vile, labelled A, and positioned securely to dry and crystallise in an oven at 65°C. 5) After 45minutes, the boiling tube, labelled
Decomposition of Baking Soda Lab Introduction Chemical reactions are essential to the understanding of chemistry, and arguably the least straightforward type of chemical reaction is decomposition. The main reason for this difficulty is that a single compound can feasibly decompose in many different ways. An example of this is NaHCO3, more commonly known as baking soda, which can hypothetically decompose in three different ways, each leaving different solid products: NaOH, Na2O, and NaCO3. Our goal for this lab was to determine which of these decomposition reactions actually occurs. The way we did this was by using a chemistry principle called stoichiometry.
On the other hand, white solid paracetamol, 100ml beaker, and 15ml of hot water, 20ml warm water, and water bath were used for the recrystallization purification technique. Evaporating dish, cold water, stirring rod, watch glass, small beaker, oven, cotton wool, and tissue were also employed in the recrystallization purification method. Method Recrystallization purification technique A portion of crude paracetamol sample was transferred into a 100ml beaker. To it, 10ml of hot water was added to dissolve it.
Experiment 4: Formal Report Preparation and Recrystallisation of Aspirin Aim of the experiment: In this experiment, a pure sample of aspirin is to be obtained through esterification to synthesise the sample, then purify the sample by recrystallisation. Lastly, determine the melting point of the sample to characterise the aspirin. Introduction: Background Aspirin (acetylsalicylic acid) is an aromatic compound that contains an ester- functional group and a carboxylic acid- functional group. Aspirin is commonly used as a pain reliever (analgesic), an anti-inflammatory, an anti-coagulant (prevent platelet aggregation) and an antipyretic (to reduce fever) pill.
In Experiment One we will be recrystallizing Benzoic Acid from water. In Experiment Two we will be recrystallizing Benzoic Acid using a solvent pair made up of Methanol and Water. The Seven step process of recrystallization consists of adding a solid organic substance into a solvent, then dissolving the chosen solute, decolorizing the solution, filtering solids, then recrystallize the solute by slowly cooling
