Introduction The objective of the experiment is to utilize a calorimeter to observe the changes of thermodynamic quantities. For Part 1: Heat of a Neutralization Reaction, 50.0 mL of 2.0 M NaOH was added and mixed with 50.0 mL of 2.0 M HCl in a calorimeter to in order to calculate the heat of neutralization for a strong acid/strong base reaction. For Part 2: Specific Heat Capacity of a Metal, an unknown metal (either A, B, or E), was heated in boiling water, and the unknown metal was placed and mixed in a calorimeter with cold tap water, and the unknown metal was identified. For Part 3: Molar Heat of Solution of a Salt, ammonium chloride salt (NH4Cl) was added and mixed in a calorimeter with deionized water, and the molar heat of solution …show more content…
The materials used during Part 2 of the experiment includes an unknown metal (either A, B, or E), an analytical balance 200 mL of tap water, a 400 mL beaker, a hot plate, 50.0 mL of cold water, and a calorimeter. The materials used during Part 3 of the experiment includes 50.0 mL of deionized water, 2 g of NH4Cl, an analytical balance and a …show more content…
Graph of Temperature (°C) vs. Time (seconds) of NH4Cl solution in a calorimeter with deionized water.
Discussion, Conclusion, and Focus Questions
The heat of neutralization for a strong acid/ strong base reaction such as 50.0 mL of 2.0 M NaOH neutralized with 50.0 mL of 2.0 M HCl is -33.86 kJ/mol, and is an exothermic reaction.
The identity of the unknown metal, e, was found to be copper because the specific heat capacity of the unknown metal, e, was 0.314 J/g°C, and according to “Table: Specific Heat Capacities of Some Substances” (Smeureanu & Geggier, 2016, p. 132) was closest to the value of 0.385, in which the substance is copper.
The molar heat of solution of ammonium chloride salt was found to be 9.6 kJ/mol and is an endothermic reaction. Because the literature value of NH4Cl is 14.78 kJ/mol, there may be various possible experimental errors in which the NH4Cl, was not dissolved and mixed thoroughly in the water, insulation errors of the calorimeter, faulty thermometers resulting in inaccurate readings, and measurement errors.
References
Smeureanu, G., and Geggier, S. “General Chemistry Laboratory”, Hunter College. N.Y. 2015, pp.129 - 134.
Post-Lab Assessment
Thermodynamics is essentially how heat energy transfers from one substance to another. In “Joe Science vs. the Water Heater,” the temperature of water in a water heater must be found without measuring the water directly from the water heater. This problem was translated to the lab by providing heated water, fish bowl thermometers, styrofoam cups, and all other instruments found in the lab. The thermometer only reaches 45 degrees celsius; therefore, thermodynamic equations need to be applied in order to find the original temperature of the hot water. We also had access to deionized water that was approximately room temperature.
We began this investigation by suiting up in lab aprons and goggles, we then gathered our materials, found a lab station and got to work. We decided to start with the magnesium in hydrochloric acid first, we measured out 198.5 L of HCl and put it in the foam-cup calorimeter and took initial temperature reading. We then selected a piece of magnesium ribbon and found its mass: 0.01g. This piece was placed in the calorimeter and the lid was shut immediately to prevent heat from escaping. We “swirled” the liquid mixture in the calorimeter to ensure a reaction, and waited for a temperature change. After a few moments, the final temperature was recorded and DT determined.
Well, this looks like its using some calculations so what I would do is take my 0.045 M and equal it to the 0.25 mL of NH3 and multiply that by 45.0 mL and multiply it by 10 with an exponent of negative 3. Once all of that is multiplied together we should get an answer of 0.01135 moles of our HCI. Now we can find our “Concentration” Which means we would divide our moles (0.01125) to our vol in liters which is 0.025, once we do that, we get an answer of 0.045M of our NH3. Well, since we are on the topic of pH we know that we can use the formula: pH = -log (H3O+). Then what we would do is plug everything into the formula: pH equals -log (2.4 multiplied by 10 (with an exponent of -5). Once we find the answer to this and we add up all of our calculations, we can come to a conclusion that the answer is: 4.6197 as our pH.
The first step that I did to find the number of grams water can be produced when 11.7 moles of ethane that reacts with the excess oxygen gas was to balance the equation like this 2 C2H6 + 7 O2 ----> 4 CO2 + 6 H20. The second step that I did to find the number of grams water can be produced when 11.7 moles of ethane that reacts with the excess oxygen gas was to find the mole ratio which is 2 moles of C2H6 : 6 moles of H20. The third step that I did to find the number of grams water can be produced when 11.7 moles of ethane that reacts with the excess oxygen gas was to multiply this by the mole ratio like this 6 moles of water / 2 moles of ethane * 11.7 moles of ethane = 35.1 moles of water. The fourth step that I did to find the number of grams
During an intense game, athletes need a way to soothe their acute injuries leading them to the instant cold packs in their team’s med kit as fans huddle under blankets clutching hot packs between frigid fingers. What these two groups don’t realize is that they are utilizing chemical reactions in order to either expel or absorb heat. Chemical reactions that were discovered and utilized by inventors to create the very packs they are using. The chemicals inside each respective pack have various properties and applications that make them useful in their thermochemistry reactions. The compounds used are salts including sodium acetate and calcium chloride for hot packs and ammonium nitrate for cold packs.
Chemistry Proposal: Bomb Calorimeter Introduction: A calorimeter is an object used to measure the heat of chemical reactions. The calorimeter is very accurate because it prevents heat loss. There are many types of calorimeters such as Simple calorimeter which consist of thermometer attached to a container (cup or plastic container), or Bomb calorimeter which is a more advanced and can measure under higher temperature.
Which type of nut has the highest number of calories? Purpose The purpose of this experiment was to test weather peanuts, almonds, ore pecans had the highest number of calories by using calorimetry and which type of nut a person would most likely want to eat. Background information
Specific heat capacity of aqueous solution (taken as water = 4.18 J.g-1.K-1). T = Temperature change (oK). We can thus determine the enthalpy changes of reaction 1 and reaction 2 using the mean (14) of the data obtained. Reaction 1: H = 50 x 4.18 x -2.12.
In this experiment, water is heated with a metal and placed into water at room temperature. The results will be the heat change between the metal and the water at room temperature explaining that energy cannot be created nor destroyed. Introduction: Specific heat is the heat required to raise the temperature of the unit mass of a given substance by a given amount. Specific heat is another physical property of matter.
Investigating the effect of temperature on the reaction between Sodium Thiosulphate (Na2S2O3) and Hydrochloric Acid (HCl)
Specific heat capacity is measured in Jg^(-1) K^(-1) (or kJ〖 kg〗^(-1) K^(-1) ). Compare the specific heat capacity of water with a range of other solvents. Complete the following table Substance Specific Heat Capacity ( Jg^(-1) K^(-1) ) Water 4.18 Ethanol 2.44 Benzene 1.05 Toluene 1.13
Radiators, like the one seen on the right, are common sights in homes today. They’ve cycled in and out of popularity over the decades, coming back into play recently as stylish additions in home renovation. However, not many people understand how chemistry is involved with a radiator. The thermochemical equation used is quite simple to understand, as radiators provide heat simply by heating up water and radiating heat from metal coils with steam in them. Radiators come in many sizes, shapes, and styles, and play a distinctive role in the history of central heating.
Neutralization Experiment AIM:- To investigate how heat is given out in neutralizing sodium hydroxide (NaOH) using different concentrations of Hydrochloric Acid. Background Information:- Substances that neutralize acids are called alkalis. An acid is a substance that forms hydrogen ions (H+ ) when placed in water. It can also be described as a proton donor as it provides H+ ions. An example of an acid is hydrochloric acid (HCl), Sulphuric acid (H2SO4) etc.
The Effect of Temperature on the Rate of Reaction Between Hydrochloric Acid and Calcium Carbonate
Indirect Calorimetry estimates the energy expenditure of the human body through measurements of expelled gases. Indirect calorimetry is not quite as accurate as direct calorimetry, which takes measurements of heat dissipated from the human body using heavy equipment, but it is less expensive to conduct experimentally, and provides one with the ability to measure oxygen consumption and carbon dioxide production. With these measurements, one gets a look into the overall aerobic physical fitness of the individual and their maximum oxygen uptake. Indirect calorimetry can also determine the primary source of energy being used using the Respiratory Exchange Ratio (RER). RER is non-invasive and provides information regarding the metabolic contribution of fat or carbohydrates.