More hydrogen bonds means a higher boiling point as these bonds are quite strong and need to be broken before the molecule can become a gas.…
In the liquid state the forces of attraction among particles are great enough that disordered clustering occurs.…
The alcohol heated up in a shorter amount of time than the water due to water’s high specific heat. The slow heat up of the water is also by the cause of water’s high heat of vaporization. High specific heat is a property of water in which water absorbs a lot of heat before its temperature increases, and releases a lot of energy before the temperature decreases. High heat of vaporization is a property of water in which a large amount of energy is needed to split water molecules small enough that they turn into water vapor. These two specific properties are important to cellular structure because they prevent organisms from exploding when energy is absorbed into their bodies, like how alcohol explodes when heated to a certain point. This prevention of cellular explosion allows organisms to complete tasks, including traveling, working, preparing food, and other actions, without fear of dying from heat exhaustion or cellular…
Evaporation, the process by which molecules undergo the a spontaneous transition from the liquid phase to the gas phase. Evaporation is the opposite of condensation. The remaining residue in the evaporation cup is the substance that had been dissolved in the solvent.…
The boiling point reflects the strength of forces between molecules. The more tightly bonded the molecules are, the more energy is required to convert them into gases. These forces are called intermolecular forces. There are 3 types, dispersion forces, dipole-dipole and hydrogen bonding. The influence of these attractive forces will depend on the functional groups present. For example heptane has boiling point of 98.4 degrees (1) and 1-hexanol has boiling point of 157 degrees. (2)…
* Heating a liquid causes the particles to move faster and faster as temperature increases. Eventually, the particles will flow so fast that the attractions they have for each other are unable to hold them together. At this point, a different temperature for different substances, the particles will separate from each other and will reach the gas phase.…
When a substance is undergoing a phase change but the temperature stays the same the energy is in the form of latent hear of fusion (melting) or latent heat of vaporization. If a substance is changing from solid to liquid then it absorbs heat from the surroundings in order to melt breaking the bonds that hold the molecules together. Gas to liquid is condensation which heat is emitting out of the substance and being removed.…
Intermolecular forces determine how easily s compound can evaporate. The stronger the force, the more difficult it is to change the state of matter. 1-butanol has the strongest intermolecular force due to its molecular weight and hydrogen bond, and this is why it has a low change in temperature of 1.4°C. N-pentane has the weakest intermolecular force due to its molecular weight and only force being London dispersion force. This is why n-pentane has a high change in temperature of 16°C. In conclusion, the change in temperature is determined by the strength of intermolecular forces.…
Hypothesis: It was predicted that methanol would have the highest molar heat of combustion, decreasing as the chains become longer.…
The increase of temperature was a result of the hydrogen bonding between the elements. Hydrogen bonding consists of the attraction of hydrogen atoms bonded to N, O or F atoms in adjacent molecules. Depending on the possibilities of hydrogen bonding and the solubility of the solution changes the energy transfer between elements.…
As a liquid evaporates, it lowers the temperature of the substances around them, because evaporation is an endothermic process. In the graph, each substance has a different curve. Some lowered the temperature much more than others. This is because different substances require differing amounts of energy to evaporate. To test this, the temperature change from the evaporation of 4 different alcohols was measured and compared, along with cyclohexane. Methanol had the largest change in temperature, 18.9 ºC. This indicates that methanol has the weakest intermolecular attractions out of the 4 alcohols, because it evaporated the most. This may be because methanol is a small molecule so it has less electrons and therefore is not as polarizable as…
I predict that octanol will release the most heat energy. This is because there is more bond energy in that molecule than the other alcohols.…
We also need to understand the specifics of combustion, which is the chemical process of burning specific compounds and other items, and the specific heat capacity - the amount of thermal energy needed to increase the temperature of a given substance. Furthermore, determining the heat of combustion to compare to the values of other hydrocarbons - elements made entirely out of hydrogen and carbon - is very useful for the reasons listed above. As we know, the measurement of the quantity of heat exchanged of any type of thermal energy released is known as calorimetry - an entirely different science than we are used to. We are using each of these concepts throughout the lab experiment and are continuing to further our knowledge of each as…
‘Kinetics’ is the study of chemical reactions. The speed of a reaction can vary depending on many variables such as the nature of the reactants, particle size, concentration and temperature. For a chemical reaction to occur, there must be a collision between reactants. The reaction rate is slower when the reactants are large and complex molecules because it takes longer for the molecules to combine together creating a chemical reaction. More than 2000 years ago, Democritus, who was a philosopher from Greece suggested that matter is made up of tiny particles too small to be seen. He thought that if you kept cutting a substance into smaller and smaller pieces, you would eventually come to the smallest possible particles.…
2. Figure 13.6a eventually moves into the air. The conversion of a liquid to a gas or vapor is called vaporization. When such a conversion occurs at the surface of a liquid that is not boiling, the process is called evaporation. Most of the molecules in a liquid don’t have enough kinetic energy to overcome the attractive forces and escape into the gaseous state. During evaporation, only those molecules with a certain minimum kinetic energy can escape from the surface of the liquid. Even some of the particles that do escacape collide with molecules in the air and rebound into the liquid.…