There is one mole of OH- in the solution since NaOH goes to Na+ and OH-. Trial 1: 25.65mL NaOH x 0.100mol/1000mL = 2.57 x 10-3 mol NaOH = 2.57 x 10-3 mol HA = 2.57 x 10-3 mol H+. The equivalent mass is 0.356g Acid / 2.57 x 10-3 mol H+ = 139g/mol H+ Trial 2: 49.57mL NaOH x 0.100 mol / 1000 mL = 4.96 x 10-3 mol NaOH = 4.96 x 10-3 mol HA = 4.96 x 10-3 mol H+. The equivalent mass is 0.644g Acid / 4.96 x 10-3 mol H+ = 130.g/mol H+ Average = (139g Acid / 1 mol H+) + (130.g Acid / 1 mol H+) / 2 = 135g/mol H+. The average equivalent mass for the acid is 135g/mol H+.
Introduction Strong acids and strong acids both dissociate completely in water forming ions. However, strong acids donate a proton to form H3O+ along with a conjugate base and strong bases accept a proton to form OH- along with a conjugate acid. The chemical behavior of acids and bases are opposite. When they are together, their ions cancel out and form a neutral solution. In this experiment, HCl and NaOH will react to form NaOH and H2O with these two steps: The overall reaction is: Both Na+ and Cl- ions combine to form NaCl.
The NaH2PO4 and Na2HPO4 powdered were weighted by using weighing machine, followed the mass that has been calculated in step (3). The NaH2PO4 and Na2HPO4 powdered were mix in a 500 mL beaker. 500 mL of distilled water were measured by using a 500 mL measuring cylinder, then is poured inside the 500 mL beaker containing both the powdered. The mixture were stirred by using a glass rod until the mixture is fully dissolved. The solution were tested by using calibrated pH meter to get the pH value of the solution.
The molar mass of a volatile liquid can be obtained by measuring the temperature, pressure, mass, and volume in a gaseous state. The equation used to determine the molar mass is derived from the Ideal Gas Law equation. The objective of this experiment aims to determine the molecular mass of a
The sample was transferred to a 250 ml conical flask kept in water bath for alkali treatment. 75 ml of 17.5% caustic soda was measured using a measuring cylinder at 20°C. 15 ml of 17.5% NaOH was added and fibres were macerated gently with a flattened glass rod for 1 minute. 10 ml more NaOH was added and the solution was mixed for 45 seconds. 10 ml NaOH was again added and mixed for 15 seconds to make lump free slurry.
The volumetric flask was then filled up to its 100 mL mark with deionized water. The buret was washed out with dionized water and then with the strong base NaOH before being filled up with NaOH. About 20 mL of the unknown weak acid was pipetted into a beaker. The starting volume of the NaOH in the buret was recorded before about 4 mL of the strong base was titrated into the weak acid solution. The final volume was recorded.
Summary Determining the concentration of a liquid can be a tricky process involving complex procedures if it were not for science’s ability to test a substance’s absorbency through spectrophotometry. The experiment was carried out to discover the concentration of Red Dye #40 in several common soft drinks. The samples of the dye were diluted, and tested using a spectrophotometer. The absorbencies of these samples were then recorded, and a standard line curve with the concentration equation and R2 value was created with these results. Using the absorbencies of the dye samples, the concentrations of the soda samples were determined using the slope equation provided by the graphing software.
Next 15M NH4OH “ammonium hydroxide” (4mL) was added to the volumetric flask. Then the flask was filled the rest of the way with distilled water to the mark. Similar steps were taken for the rock solution. The rock solution from the prior lab was filtered into a volumetric flask (100mL), then 15 M NH4¬OH (8mL) was added to the flask. After that, the flask was filled to the mark with distilled water.