• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4

# Calorimeter lab. What is the change in enthalpy for magnesium after the reaction with vinegar?

Extracts from this document...

Introduction

﻿Introduction: The first law of thermodynamics states the total energy of an isolated system cannot be created or destroyed. Since chemical energy is the sum of heat plus work many chemical reactions involve the evolution of heat or production of work. An example is a car engine that converts the chemical energy stored in gasoline into heat and work. This heat that is exchanged can be measured with an apparatus called calorimeter. A calorimeter is an insulated vessel preventing the heat from escaping into the surrounding. The thermometer is used to measure the temperature change and the stirrer is used to ensure the heat is uniformly distributed. ...read more.

Middle

The apparatus was moved to the front of the class where the teacher set up the thermometer attached to the laptop showing the temperature. A Styrofoam cup with two holes for the thermometer and another for the stirring rod was set up and was placed on top of the apparatus as tightly as possible so not a lot of the gas can escape. The initial temperature was measured using the thermometer. The top was removed, the magnesium was added and quickly the top was placed back on to the top. The stirring rod was used to mix the solution inside the calorimeter. The thermometer connected to the computer showed the temperature increase and decrease as a graph. ...read more.

Conclusion

mol ΔH = -Q ÷ nmg = -2366.4704 J ÷ 0.0082 mol = -288.59 kJ/mol The change of enthalpy is -288.59 kJ/mol for the magnesium. Conclusion The hypothesis was right because the change of enthalpy of the magnesium is -288.59 kJ/mol. A lot of heat is released from this reaction. 0.2 g of magnesium was used with 20.0 mL of vinegar. The initial temperature of the calorimeter was 24.7 °C and the finial being 52.7 °C. The magnesium reacts with vinegar (CH3COOH) because of the oxygen present. The reactivity of the magnesium increase as the oxygen level increases. This single displacement reaction of the magnesium and the vinegar reacts and forms hydrogen gas. Reference: Biology 12. Toronto: McGraw-Hill Ryerson, 2011. Print. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Organic Chemistry section.

## Found what you're looking for?

• Start learning 29% faster today
• 150,000+ documents available
• Just £6.99 a month

Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

# Related AS and A Level Organic Chemistry essays

1. ## Find the enthalpy change of combustion of a number of alcohol's' so that you ...

each experiment: Energy transferred to water by burning fuel (Kj mol-1)= (mass of water (g) x temperature rise (0C) x 4.2 (J)) From this above formula the enthalpy change of combustion can be worked out for each experiment by finding out the amount of moles of fuel burnt, using this formula: Moles = (Mass/Relative Molecular Mass)

2. ## The aim of this experiment is to produce Aspirin. This is an estrification in ...

+ 0.5632% By working out the total percentage error, the confidence limit can be calculated. Actual weight of aspirin = 0.3086g Total % error = 0.5632% 0.5632% of 0.3086g = 0.0173 (0.05632 x 0.3086) 0.3086 + 0.0173 = 0.3259 0.3086 - 0.0173 = 0.2913 This means the mass of aspirin

1. ## investigating the amount of ascorbic acid present in fruit

by 10.00 (which was the amount of fruit sample that I used). This worked out to the value of 0.064mg of vitamin C in the orange sample. Lime: 4.93 = 0.492mg of vitamin C in the lime sample 10.00 Here I divided the mg of vitamin C in the lime sample (that was found to be 4.93mg)

2. ## Comprehensive and Detailed Chemistry notes

-- The pH function is defined as: pH= -log10[H+] -- [H+] means concentration of H+ -- When bases are added to water, the hydronium ion and hydroxide ion concentrations multiply to give a constant 1.0 * 10-14 -- This is known as the water constant (Kw)

1. ## Investigating the Enthalpy Changes of Combustion of Alcohols.

(See below graph) This means that the lower the temperature rise, the smaller the heat losses are. I have decided to keep the temperature rise around 10 �C. The overall heat capacity of the apparatus does not only depend on the temperature rise, as the amount of matter in the surroundings will also affect the overall heat capacity.

2. ## Determination of the Enthalpy Change of a Reaction

/ 177.8 = 60.4% Considering the scatter diagrams, they show the expected positive correlation. This is, the more reagents added, the more products there are. The amount of products formed is directly proportional to the temperature change since this is the amount of energy transferred as a result of the breaking and forming of intra-molecular bonds.

1. ## I am going to investigate the difference in enthalpy of combustion for a number ...

2062 745.5 1480 1852 The total energy required to break The total energy released in the forming the bonds in the reactants is of the bonds in the products is 2807.5 DH/KJ mol-1 3332 DH/KJ mol-1 the difference between the reactants and products is -524.5 DH/KJ mol-1 From above, there

2. ## Comparing the enthalpy changes of combustion of different alcohols

In other words, the enthalpy change of combustion of an alcohol increases as the length of the carbon chain is increased, due to an addition of a CH2 group. Risk Assessment As during this experiment I will be handling potentially harmful chemicals, several safety precautions must be made to ensure the safety of myself and others around me.

• Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to