Standardization of NaOH solution Accurately weigh out a sample of approximately 0.3-0.4 g of primary standard potassium hydrogen phthalate, KHPh, which has been previously dried at 120°C. Do not use more than 0.4 g. To obtain an accurate mass, weigh the sample on weighing paper, slide it into a clean (but not necessarily dry) 250 mL Erlenmeyer flask and reweigh the paper to account for any KHPh that may remain on it. Dissolve the KHPh sample in about 50 mL of CO2-free water and add 2-3 drops of 0.1% phenolphthalein indicator. Begin adding the approximately 0.1 M sodium hydroxide solution from the buret while continuously swirling the flask contents. Do not open the stopcock completely.
Diazotized Sulphanilic Acid 1. Dissolve 1.1 g of anhydrous sodium carbonate in 50 mL of water in a 100 mL conical flask. 2. Add 4 g of sulphanilic acid to the solution and heat it until it dissolves. A small amount of suspended material may render the solution cloudy.
How does temperature affect the rate of reaction of amylase? 3. Hypothesis a. As the temperature increases, the rate of reaction of amylase also increases. After it reaches the optimum temperature, the rate of reaction will start to decrease until all the enzymes are denatured.
Problem: How does the temperature of water used to dissolve an Alka-Seltzer tablet affect the amount of time it would take for the tablet to completely dissolve? An Alka-Seltzer tablet is a medicine tablet made with baking soda used as a pain reliever for “headaches, body aches, pain, heartburn, acid indigestion, and sour stomach” (Alka-Seltzer Tablets). It is put into water, left to dissolve and then consumed. When an Alka-Seltzer tablet is dropped into h20, a chemical reaction immediately takes place and produces bubbles made out of carbon dioxide as a product of the collision (Olson 2). When in its original powder (dry) form, the Alka-Seltzer’s two main ingredients: citric acid and sodium bicarbonate are just there and not reacting to each
It can be thought of as a measure of the difficulty of removing electrons or the strength of the electrons that is bounded. Consequently, the higher the ionization energy, the more difficult it is to remove an electron. Thus, ionization energy is considered as an indicator of an atom’s reactivity. This type of energy is usually expressed in kJ/mol. Similarly as the atomic radius, the ionization energy follows a trend on the periodic table of elements.
To determine the rate of reaction there are many method to be used for example, measuring the mass after the product has been added and measuring the difference in mass on the duration of a digital scale. Another method, which will be used in this experiment is using a gas syringe to measure the volume of the gas which has been produced. The cylinder inside, will be pushed out to show a quantitative presentation of the volume produced by the reaction. Hypothesis I predict that the more baking powder added to the vinegar, the more reaction will take place causing for more gas to be produced per 10 seconds. There will be a gradual decrease in difference between volume in gas per 10 seconds over the duration of time.
The supernatant was assayed for SOD activity by following the inhibition of epinephrine auto-oxidation. 0.5ml of sample was diluted with 0.5 ml of distilled water, to this 0.25 ml ethanol, 0.5 ml of chloroform (all reagents chilled) was added. The mixture was shaken for 1 min and centrifuged at 2000 rpm for 20 min. The enzymatic activity in supernatant was determined. To 0.05 ml of carbonate buffer (0.05 M, pH 10.2) and 0.5 ml of EDTA (0.49 M) was added.
Experiment 1: Materials: • Alka-Seltzer tablets • Empty and clean water or soda bottles (12 oz to 24 oz) • Balloons • Water • Clock • Stove top Procedure: 1. Pour a sufficient amount of water (about 16 oz) into a small pot and place on the stove at high heat. 2. Watch the clock and after 30 seconds take the water off the heat. 3.
That is, the higher the temperature of the solvent (water), the more solute (salt) that will dissolve in it. In this experiment, we will study the solubility of potassium nitrate (KNO3) in water. You will dissolve different quantities of this salt in a given amount of water at a temperature close to its boiling point. Which solution will be