C. The final pH is 7. D. Water is produced. 2. Which salt could be prepared by a method involving crystallization as a final stage? A. barium sulphate B. calcium carbonate C. silver chloride D. sodium nitrate 3.
Titration Lab Period 3 5/20/12 Objective: The main objective of this lab was to determine the amount of sodium hydroxide needed to neutralize 10 milliliters of hydrochloric acid. We also had to calculate the molarity of the sodium hydroxide using our data. Concepts: Some different concepts used in this lab: indicators, titration formula, titration curves, pH levels, acids, and bases. Materials: Materials used in this lab: a 250mL beaker, ring stand, burette, Erlenmeyer flask, stop cock, burette clamp, 10mL HCL, 10mL NaOH, 3 drops of phenolphthalein, and pH paper. Procedure: 1.
The aim of this experiment is to find the formula of magnesium oxide. Magnesium burns bright red but when it mixes with oxygen will form a white solid magnesium oxide (magnesium looks doll red). The mass of magnesium oxide will be more than the mass of magnesium because oxygen from the air joined with magnesium. To find out how much oxygen has joined with the magnesium, we just need to weigh the magnesium oxide after reaction and compare the value with mass of the magnesium before reaction. To work out the formula of the magnesium oxide, we need relative atomic masses and number of moles of magnesium and oxygen.
At this point, the sponge contains residual magnesium and magnesium chloride. Thus, the sponge is crushed and treated with hydrochloric acid and water in order to eliminate excess magnesium and magnesium chloride. Another method for removing the residues is the high temperature vacuum distillation. Although the hunter process is similar to the Kroll process, the hunter process is more expensive and it is only used for the production of small amounts of high purity powder. The hunter process follows the same steps as the Kroll process except for the fact that sodium is added to the vessel and therefore, NaCl is the salt that is entrapped in the pores of the sponge formed.
NAMING CHEMICAL COMPOUNDS This paper will explain the instructions for the process of naming the five chemical compounds. The names of these compounds are; Type 1: binary ionic, Type 2: binary ionic, Type 3: binary covalent, Type 4: ternary ionic, and Type 5: acids. Type 1: Binary Ionic Type 1 Binary Ionic compounds consist of a metal and a nonmetal. They usually contain a main – group metal. Main – group metals usually for one cation (positive ion).
Contents Page Experiment 1 Calibration of a 25-mL Pipette 1 Experiment 2 Volumetric Analysis 3 Experiment 3 Experiment 4 Experiment 5 Gravimetric Determination of Nickel Sodium Acid Salt of Heptaoxodiphosphoric Acid Synthesis and Stoichiometric Analysis of Hexaamminenickel(II) Chloride 5 6 9 Experiment 1: Calibration of a 25-mL Pipette Background The graduation mark on a pipette being usually made at 20°C (whereas room temperature is much higher than this), the volume of the pipette must be calibrated before any volumetric analysis is carried out. Otherwise, the error in the graduation mark may exceed the error allowed in a measurement. A pipette is designed to deliver only one fixed volume of a liquid and it is calibrated for this volume only. Accuracy to two decimal places in mL is generally possible. The pipette is calibrated by weighing distilled water in it at room temperature, and then calculating the volume from the weight of water in air.
TITRATION OF AN ACID (A PREPARED STANDARD SOLUTION OF KH₅O₄C₈) AGAINST A BASE (NAOH) USING PHENOLPHTHALEIN AS AN INDICATOR BY GRACE The aim of this experiment is to prepare a standard solution of potassium hydrogen phthalate (KH₅O₄C₈) and then use it to calculate the concentration of sodium hydroxide by titrating the acid (KH₅O₄C₈) against the base (NaOH). Before the whole experiment could take place, some apparatus were needed which included the following; A weighing balance, burette, pipette, a conical flask, clamp and then the setup was as below; THEORY To calculate for the moles of KH₅O₄C₈, I used n (mol) =m (g)/M (gmol⁻ⁱ (JOHN GREEN AND SADRU DAMJI, PG 6 OF CHAPTER 1.THIRD EDITION). Whereby m=mass of the acid, M=molar mass of the acid and n=number of moles. Molar mass of KH₅O₄C₈ is 204.1g/mol and its mass is 1g Therefore=1g/204.1gmol⁻ⁱ n=0.0048996mol Further more, to calculate for the concentration of the acid, I used C(moldm⁻3.) =n (mol)/v (dm3) Whereby c=concentration, n=number of moles and v=volume used.
I predict that the lab technician’s Sodium Hydroxide will be a better solution than the one I made myself. So my prediction is that it will take more Sulphuric Acid to neutralise the solution when I use the Sodium Hydroxide that I made myself. Equipment List • Sodium Hydroxide Pellets • Phenolphthalein Indicator Solution • Dilute Sulphuric Acid • Distilled Water • Weighing Boat • Scales • Volumetric Flask • Conical Flask • Funnel • 25ml Pipette • Burette • White Tile • Spatula • Goggles • Gloves Method for Standard Solution Measure out 10 grams of Sodium Hydroxide pellets in a weighing boat using the scales. Place the pellets into the volumetric flask and add distilled water to make the solution 250ml. Swirl the flask to ensure that all the pellets have dissolved.
Na and Mg are electropositive so they lose electrons in reactions and oxygen atoms form oxide ions O2-. Oxide ions are strong bases because they can accept protons from water. So, sodium peroxide and magnesium oxide are basic. Al2O3 is amphoteric as it has reactions as both a base and an acid. Si, P, S and Cl are increasingly electronegative.
The watch glass was removed with the beaker tongs. Using a rubber bulb and a stirring rod to stir the solution continuously, 15.00mL of .25M BaCl2 solution was added to the solution in the beaker. The watch glass is replaced and the solution is keep hot but not boiling for 15 minutes. The precipitate was allowed to settle. When the liquid above the precipitate was clear, the solution was tested for completeness of precipitation when a few drops of BaCl2 solution were added from a pipette.