For reaction (II) Pb (NO3)2 + 2KI -> PbI2+2KNO3 Lead nitrate is soluble, so it gets written as ions. The same goes for potassium iodide and potassium nitrate. Complete Ionic equation: 2 K+1 + I-1 + Pb2+ + NO32- -> PbI2 + 2K+1 + NO3-1 Net Ionic Equation: Pb+2 + 2 I-1 -> PbI2 Warm-Up Exercise 2 In this lab you will mix 25 mL of 0.05M lead nitrate with 1.4 mL of 0.025M sodium carbonate. After the reaction occurs, you will filter the solution to remove the precipitate. You will then test the remaining solution for excess lead ion and for excess carbonate ion… Imagine that you mix the two volumes and then freeze frame the reaction so the it does not proceed: 1.
Simple Distillation and Gas Chromatograpy In this experiment we demonstrated the methods for purification of volatile compounds and that gas chromatography may be used to quantitatively determine the relative proportions of volatile compounds in each sample. To do this, we performed a simple distillation of a new mixture of Hexane-Heptane. We then collected three different fractions from the distillation, recorded the temperatures each time. Then using chromatograms, we compared the three fractions we obtained and determined the percentages of Hexane-Heptane for each fraction collected. In a gas chromatogram, the peak areas are considered to be directly proportional to the amound of sample passing the detector in the gas chromatogram.
A spectrophotometer may be used to determine if iron and chromium are in the sample, but magnesium neither absorbs nor emits light energy in the 200-900nm region of the spectrum so it can not be determined by a spectrophotometer. Magnesium must be isolated and precipitated through the process of extraction.
However, boron has an electronegativity that is very similar to hydrogen, meaning there is likely very little ionic character in the hydrogen to boron bonds, and as such this Lewis structure, though it does not fulfill the octet rule, is likely the best structure possible for depicting BH3 with Lewis theory. One of the things that may account for BH3's incomplete octet is that it is commonly a transitory species, formed temporarily in reactions that involve multiple steps. Let's take a look at another incomplete octet situation dealing with boron, BF3 (Boron trifluorine). Like with BH3, the initial drawing of a Lewis structure of BF3 will form a structure where boron has only six electrons around it (Figure 6). Figure 6 If you look Figure 6, you can see that the fluorine atoms possess
A circumstance without any of the evidences present concludes that a chemical reaction has not occurred and thus a displacement reaction has not taken place. Figure 1 Figure 1 chlorine + sodium iodide iodine + sodium chloride (non-metal) (compound) (non-metal) (compound) Cl2 + 2 NaI I2 + 2 NaCl Figure 2 Figure 3 Figure 3 (Source of Figure 3: http://vinstan.wikispaces.com/Chapter+3+++++Chemical+Reactions) Purpose: The main objective of Activity Series of Metals is to determine the reactivity of common metals. For this lab we should be able to find out and predict the products that come from a
Introduction A titration was carried out in this experiment to find the concentration of hydrochloric acid is an unknown solution. The aim of this experiment is to determine the number of moles of sodium hydroxide in hydrochloric acid and then to determine the number of moles of sodium hydroxide present in gastric juices. Titration, or volumetric analysis, is a common laboratory procedure for the analysis of substances and solutions. In a titration, the analyst determines the volume of a solution, called a titrant, that reacts exactly with a known weight or volume of another substance. This reaction is carried out by adding a solution of reactant hydrochloric acid from a burette to a solution of sodium hydroxide until just sufficient of hydrochloric acid has been added to react with all of the sodium hydroxide.
Gravimetric Determination of Sulfate Purpose The purpose of this lab is to determine the percentage of sulfate in the hydrate by precipitating the sulfate as barium sulfate. Materials Filler paper Sodium sulfate Graduated cylinder Bunsen burner Watch glass Beakers (250 mL, 400 mL) Rubber bulb Graduated pipette Beaker tongs Funnel Filter Paper Sodium Sulfate Drying oven Wash bottle Stirring rod Silver nitrate Hydrochloric acid Distilled water Small test tube Procedures First, .4861 grams of sodium sulfate was placed into a clean 400mL beaker. Exactly 200mL of water and 1mL of HCl was added to the same beaker. A watch glass was placed on the beaker and the solution was heated using the Bunsen burner to a gentle boil. The watch glass was removed with the beaker tongs.
Hess's Law Lab Report Purpose Data and Observations Part I Heat of Solution of Solid Sodium Hydroxide Table 1 Original temperature of water (t1) 21.0ºC Final temperature of solution (t2) 26.0ºC Temperature change (t2-t1=∆t) 5.0ºC Mass of 100 mL of water 100.0g Heat evolved by reaction 2092J Mass of NaOH(s) 2.0g Moles of NaOH 0.05001250313 moles Energy per mole of NaOH 41829.52 J/mole ∆ H1 (kJ/mole) NaOH 41.83 kJ/mole Part II Heat of Reaction between Hydrochloric Acid and Sodium Hydroxide Solution Table 2 Original temperature of HCl(aq) 21.0ºC Original temperature of NaOH(aq) 21.0ºC Average original temperature (t1) 21.0ºC Final temperature of solution (t2) 34.5ºC Temperature change (t2 - t1 = ∆t) 13.5ºC Total mass of solution (assume 1mL = 1 g) 100.1g Heat evolved by reaction 5648.64 J Molarity of NaOH solution 2.0 M Volume of NaOH solution 0.05 L Moles of NaOH 0.1 moles Energy per mole of NaOH 56486.4 J/mole ∆H2 (kJ/mole) NaOH 56.49 kJ/mole Part III Heat of Reaction between Hydrochloric Acid and Solid Sodium Hydroxide Table 3 Original temperature of HCl(aq) (t1) 21.0ºC Final temperature of solution (t2) 34.0ºC Temperature change (t2 - t1 = ∆t) 13.0ºC Mass of HCl (assume 1 mL = 1g) 101.46g Heat evolved by reaction 5513.34 J Mass of NaOH(s) 2.0g Moles of NaOH 0.05001250313 moles Energy per mole of NaOH 110239.23 J/mole ∆H3 (kJ/mole) NaOH 110.24 kJ/mole Questions and Calculations Reaction 1: ∆T=26˚C-21˚C ∆T= 5˚C Cw=4.184J/(g˚C) qw=(100.0g)(4.184J/(g˚C))(26˚C-21˚C) qw=2092J -qrxn=qsolution qrxn=-2092J nNaOH=2.00g×(1 mole)/39.99g=0.05001250313 mols ∆H=qrxn/n=(-2092 J)/(0.05001250313 mols)×1kJ/(1000 J)= ∆H=-41.83 kJ/mole Reaction 2: mass=48.9g+54.2g=103.1g ∆T=34.5˚C-21˚C=13.5˚C Cw=Csolution=4.184J/(g˚C) qsolution=(103.1g)(4.184 J/(g˚C))(34.5˚C-21˚C) qsolution=5823.5 J -qrxn=qsolution
Title : Reaction of Carboxylic Acids Objective : To Determine The Reaction of Carboxylic Acids Procedure : As referred to Lab manual. Results: A. Salt Formation |Compound |Solvent |Solubility | |Benzoic Acid |Cold Water |Partially soluble | |Benzoic Acid |10 % NaOH |Soluble | B. Salt Hydrolysis Sodium acetate solution changed the color of litmus from red to blue. C. Reaction With Sodium Carbonate Observation : A lot of gas bubbles was released.
In this experiment the team of students must determine exactly what is in chromite sample, and also confirm the existence of all such metals that should be in the sample of chromite. The leaching technique will be used and precipitates formed via the addition of NaOH to the leach solution. The displacement of iron via zinc will also be utilized. As each metal precipitate forms in the solution, it will have to be separated from the remaining solution and the process repeated until all precipitates have been created and isolated. Next, each individual precipitate will be dissolved into an aqueous solution and ran through a spectrometer.