Objectives: The purpose of this lab is to observe the reaction of crystal violet and sodium hydroxide by looking at the relationship between concentration and time elapsed of the crystal violet. CV+ + OH- CVOH To quantitatively observe this reaction of crystal violet, the rate law is used. The rate law tells us that the rate is equal to a rate constant (k) multiplied by the concentration of crystal violet to the power of its reaction order ([CV+]p) and the concentration of hydroxide to the power of its reaction order ([OH-]q). Rate = k[CV+]p[OH-]q To fully understand the rate law, concentrations of the substances must be looked at first. The concentration is measured in molarity.
This was done by taking small amounts of the unknown acid. It was then placed into capillary tubes and inserted into the Bibby Sterilin Device. Starting with a high plateau to find a quick melting point and then proceeding to find an actual melting point. The next experiment that aided in finding more characterizations of unknown #2651145-PLF13 was equivalent weight. In order to find the equivalent weight a titration of the unknown acid had to be conducted.
Computer Additivity of Heats of Reaction: Hess’s Law 18 (1) Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. (2) Solid sodium hydroxide reacts with aqueous hydrochloric acid to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) ) + Cl–(aq) → H2O(l) + Na+(aq) + Cl–(aq) ∆H2 = ? OBJECTIVES • • • • In this experiment, you will Combine equations for two reactions to obtain the equation for a third reaction. Use a calorimeter to measure the temperature change in each of three reactions.
Explain. It is valid to conclude that a base were added, the rate of the reaction would slow down because the pressure of oxygen barely increased, meaning the enzymes were not working at a faster rate. 6. Predict what would happen if vinegar (also known as acetic acid) were added to a water solution of hydrogen peroxide and
Different compounds boil at different temperatures because each has a different, characteristic vapor pressure: compounds with higher vapor pressures will boil at lower temperatures. Boiling points are usually measured by recording the boiling point (or boiling range) on a thermometer while performing a distillation. This method is used whenever there is enough of the compound to perform a distillation. The distillation method of
To find out N2 you have to determine the mass of water produced in the reaction. This mass is the difference between the mass of initial compound (BaCl2•XH2O) and the mass of anhydrous salt (BaCl2). N2 is the ratio of the mass of the water produced in the reaction to the molar mass of
Tablet | A report based on a scientific experiment designed to investigate and compare the rates at which different forms of aspirin dissolve. | 11-11-2013 | Introduction This experiment was designed to investigate and compare the rates at which different aspirin tablets dissolve in both Water (H2O [representing saliva]) and Hydrochloric Acid (HCl [representing the stomach’s acid]). The amount of Water and Hydrochloric Acid will be kept constant between tablets, and tests. Aim To investigate and compare the rates at which different Aspirin Tablets dissolve. The different kinds of Aspirin tablets are: * Enteric Coated Tablets * Capsules * Regular Tablets * Dissolving Tablets.
The heat obtained when a known mass of alcohol or paraffin wax burns will be used to warm a measured volume of water. Enthalpy change can be defined as the amount of heat released or absorbed when a chemical reaction occurs at constant pressure. In an exothermic reaction, such as the case in this experiment, the following reaction takes place: H = H(products) - H(reactants) = negative (-ve) Specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius. The relationship between heat and temperature change is usually expressed, where c is the specific heat. The relationship does not apply if a phase change is encountered, because heat added or removed during a phase change does not change the temperature.
The only variable that is changing is the temperature meaning that the temperature and the heat of reaction have a positive correlation. If the temperature increases then the value for the enthalpy change will increase, and vice versa. All measurements, observations and calculations were carefully checked and are therefore not a source of error. One source of error could be that the calorimeter (Styrofoam cup) was uncapped and not a perfect insulator for keeping the heat from escaping. As it was uncapped some of the heat would have been lost to the air and as one of our assumptions was that the heat released by the reactions was used only to heat the water the value calculated will be off.
There is no current predicament related to Daphnia. The main focus on the experiment is to notice any differences in the heart rate of the species Daphnia. It’s needed to keep the water as neutral as possible because of the fact that Daphnia’s usual heart rate is three-hundred beats per minute (British Pharmacological Society, 2010). The heart rate can be monitored and counted in different conditions. The objective is to see if changing the water temperatures will harm the heart rate of the Daphnia.