First hand investigation of the Dissolution of Solutes Background Information Molar heat of solution * The molar heat of solution of a substance is the heat absorbed when one mole of the substance dissolves in a large excess of water. It is expressed in kJ/mol. * The specific heat of water is a constant‚ with a value of 4.18 J/ g*oC. AIM: To determine the molar heat of solution for two different solids Equipment: * A calorimeter (made using 2 Styrofoam cups with a cardboard lid)
Premium Chemistry Solution Thermodynamics
Experiment 11 Calorimetry and Hess’s Law Purpose- To determine the change in enthalpy for four reactions using calorimetry and Hess’s Law Procedures: A. Calibration of the Calorimeter 1. Obtain two copper cylinders and a Styrofoam cup with lid from your lab instructor. Check out a digital thermometer display from the storeroom window. 2. Set up a hot water bath using a 600mL beaker‚ ring stand‚ and Bunsen burner. Weigh the two copper cylinders
Premium Sodium hydroxide Thermodynamics Reagent
1. Determining the concentration of KMnO4 from the solution created by the stockroom. 16H+ + 2MnO4- (aq) + 5C2O42- (aq) → 2Mn2+ (aq) + 10CO2 (g) + 8H2O (l) Volume of potassium manganate (KMnO4) = 32.5 mL Mass of Sodium Oxalate (NaC2O4): 0.104 [KMnO4] Calculation: = (0.104g of NaC2O4)(1 mol NaC2O4 /134.0g)(2 mol KMnO4 / 5 mol NaC2O4)(1/32.5 mL)(1000 mL /1L) = 0.00955 M KMnO4 2. Using the standardized concentration of KMnO4 calculated above to find the mass percentage of the oxalate ion Equation:
Premium Chemistry Water Concentration
urban heat island effect. In scientific terms‚ it is the difference between the temperature recorded in the urban environment and the temperature recorded in its rural surroundings. Heat waves will become more frequent in the next years. The urban heat island effect is
Premium City English-language films Sun
purpose of the two experiments was to determine the fundamental effects that temperature has on the growth and survival of bacteria. During the first experiment five different bacterial broth cultures of Escherichia coli‚ Pseudomonas fluorescens‚ Enterococcus faecalis‚ Bacillus subtilis and Bacillus stearothermophilus were individually incubated at temperatures of 5‚ 25‚ 37‚ 45 and 55°C for one week in an aim to distinguish the effect temperature has on growth and survival of the five different species
Premium Bacteria
Calorimetry Lab: Determining the Unknown Metal Purpose: To determine the identity of an unknown metal Hypothesis: The unknown metal is Copper Materials: * Safety glasses * Styrofoam cup * Thread or string * Glass rod * Thermometer * 100mL graduated cylinder * Hot plate * Balance * Unknown metal * 300mL beaker Procedure: i. Mass of metal was recorded ii. Water was heated on a hot plate in beaker iii. Temperature was recorded when water reached
Premium Heat Temperature Thermodynamics
Experiment 1: Calorimetry Nadya Patrica E. Sauza‚ Jelica D. Estacio Institute of Chemistry‚ University of the Philippines‚ Diliman‚ Quezon City 1101 Philippines Results and Discussion Eight Styrofoam ball calorimeters were calibrated. Five milliliters of 1M hydrochloric acid (HCl) was reacted with 10 ml of 1M sodium hydroxide (NaOH) in each calorimeter. The temperature before and after the reaction were recorded; the change in temperature (∆T) was calculated by subtracting the initial temperature
Premium Thermodynamics Heat Specific heat capacity
CALORIMETRY AND HESS’S LAW: FINDING ΔH FOR THE COMBUSTION OF MAGNESIUM MATERIALS: 12 oz. Styrofoam cup with lid‚ thermometer‚ 50-mL and 100-mL graduated cylinders‚ weighing boat‚ 1.0 M HCl‚ 1.0 M NaOH‚ magnesium ribbon‚ magnesium oxide‚ copper wire. PURPOSE: The purpose of this experiment is to determine the enthalpy change for the combustion of magnesium: Mg (s) + ½ O2 (g) → MgO (s) ΔHrxn = ΔH combustion by determining the ΔH values for reactions which can be combined together according
Premium Enthalpy Energy Thermodynamics
CALCULATIONS Determining the amount Limiting Reagent used. nlimiting reagent = Molarity x Volume or Mass / Molar Mass Example: Limiting reagent is 5mL of 1.0 M HCl nlimiting reagent = Molarity x Volume nlimiting reagent = (1.0 [mol/L]) x 0.005 [L]) = 0.005 mol Determining the qrxn and qcal. qrxn + qcal = 0 -qrxn = qcal qrxn = ΔHrxn x nlimiting reagent qcal = Ccal ΔT qrxn = - Ccal ΔT + mcsolid ΔT (note: only if there is a precipitate formed in the reaction)
Premium Mole Product Reagent
Data and Observations: Part I Table: Metal: | Aluminum | Zinc | Iron | Copper | Mass of metal: | 27.776 g | 41.664 g | 34.720 g | 41.664 g | Volume of water in the calorimeter: | 26.0 mL | 26.0 mL | 26.0 mL | 26.0 mL | Initial temperature of water in calorimeter: | 25.3 °C | 25.3 °C | 25.3 °C | 25.3 °C | Temperature of hot water and metal in hot water bath: | 100.5 °C | 100.5 °C | 100.5 °C | 100.5 °C | Final temperature reached in the calorimeter: | 38.9 °C | 34.8 °C | 34.2 °C | 34
Premium Density Energy Heat