Also, the heat (energy) and the distance between the Bunsen burner (source of energy) and the test tube need to be under control. The sodium bicarbonate will decompose faster if the energy is higher or if the source of energy is closer to the test tube. This will be controlled by using the maximum gas and keep the position of the Bunsen burner (10 cm from the test tube) constant, this will ensure the trials to be exposed to the same energy
Discussion The ideal Van't Hoff factor for potassium chloride is 2, because the compound dissociates into its ions, K+ and Cl-. The greater the Van't Hoff factor means the more a compound lowers the freezing point temperature of the solvent it dissolves in. For a liquid to freeze it must form a lattice, a three-dimensional arrangement of particles that make up a crystalline solid, and the presence of solute particles interferes with the ability of the solvent particles to form a lattice. To compensate the system must be brought to an even lower temperature to freeze, and the more particles that are present within the solvent, the larger that freezing point depression becomes.3 Thus, the obtained value of 2.05 means that potassium chloride lowered the freezing point of water lower than what was expected. Nonetheless, the Van’t Hoff factor of calcium chloride is
Ions are charged particles. When the concentration of hydrogen ions is higher, there is lower pH. Strong acids are fully ionized however weak acids are just partly ionized in a solution. As an example, ethanoic acid is a weak acid but hydrochloric acid is a strong one. Bases produce hydroxide ions in an aqueous solution.
The data was handled accurately, values clearly labeled and calculated in the correct procedure. The procedure of reacting magnesium with oxygen was most likely the source of error. It is possible that the magnesium strip had not completely reacted with oxygen yet when I took the crucible off the burner and dropped distilled water into it. To improve this experiment, there could be better Bunsen burners: for some students, the fire was not strong enough so the magnesium strip did not glow and react. Also, there could be description or a standard time of how much oxygen should react with magnesium so that the exact mass of magnesium oxide could be
There was an increase in temperature after the concentrated sulphuric acid was added into the volumetric flask containing the iron (II) solution, the outer glass of the volumetric flask was warm. The reason why concentrated sulphuric acid was added is so that the iron (II) solution is stabilized. This is because Iron (II) is vulnerable to be oxidized but the oxidation of iron (II), 〖Fe〗^(2+) to iron (III), 〖Fe〗^(3+) is unable to take place in the presence of an acid. Sulphuric acid which is a strong acid will react with potassium permanganate solution, which is an oxidizing agent, to produce high concentration of hydrogen ions in order to convert oxygen from the potassium permanganate solution into water molecules. Therefore, diluted sulphuric acid was added to the standard iron (II) solution before titration took place.
Aim: To find out the relationship between the greater concentration of sodium thiosulfate when mixed with hydrochloric acid and the time it takes for the reaction (the time it takes for the solution to turn cloudy) to take place and to show the effect on the rate of reaction when the concentration of one of the reactants change. Introduction: The theory of this experiment is that sodium thiosulfate and hydrochloric acid reach together to produce sulfur as one of its products. Sulfur is a yellow precipitate so, the solution will turn to yellow color while the reaction is occurring and it will continue until it will slowly turn completely opaque. The reaction of the experiment happens with this formula: “Na2 S2 O3 + HCL = 2NaCl + H2O + SO2 + S” The rate of reaction of sodium thiosulfate (the time it takes for the solution to be cloudier) will be faster if its concentration is greater. In order for a chemical reaction to occur the reactant particles must collide.
This is because the time taken for the leaf to rise to the surface is dependent on the concentration of hydrogen peroxide solution. The dependent variable is the time taken for the leaf to rise to the surface. One may measure the time taken for the leaf to rise by using a stopwatch and start measuring the time as soon as the leaf is submerged in the hydrogen peroxide and stop the timing when the leaf has flipped over and risen to the surface. One may make the results as reliable as possible by repeating the experiment three times using different brassica rapa leaves of the same size in fresh sets of hydrogen peroxide. First control variable was the volume of hydrogen peroxide used, as it affects rate of enzyme
That means the non-polar molecules will spend a shorter time in solution in the mobile phase and it will slow them down on the way through the column. So over all polar molecules will travel faster through the column than non-polar molecules. The speed of the molecules going through the column is very important. Because the time it takes them to go through the column and reach the detector is the determining factor in the analysis of the compound. That time is called retention time.
Because of inhabitation property of water toward complete reaction, the methanol and water mixture is separated from the oil phase. Afterward, further methanol and acid catalyst can be added and the reaction continued for the next step. We should note that if the number of pretreatment steps be increased, the ester yield reduces owing to the solubility of ester in methanol . For that reason, in this study, we tried to reduce the FFA level through one step pretreatment to achievement high ester yield and also save the time for producing BD. After each esterification, total WCF was washed twice with hot and distilled water to eliminate any reminded acid in
This is as a result of the common ion effect. The dissolution of Ca(IO3-)2.xH2O Ca(IO3-)2.xH2O in pure water and KIO3 solution obeys Le Chatelier’s Principle. Dissolving solid calcium iodate in pure water shifted the equilibrium to the right to produce more iodine. On the other hand, dissolving solid calcium iodate shifted the equilibrium to the left to produce fewer iodate ions. Surprisingly, dissolving calcium iodate in pure water and KIO3 solution produced different Ksp values.