Cooling Rate of Certain Liquids
Scientific Investigations
Experiments to Determine the Cooling Rate of Coffee, when Milk should be Added and what Container should be Used
The aim of the first experiment was to find out and record the cooling rate of coffee under three different conditions and thus showing when milk should be added assuming you have a phone call. The three different conditions were chosen because these were the most likely situations encounted by someone who is making a cup of coffee. We used Tain instruments to accurately calculate the temperatures in the three beakers chosen and we then recorded these results and used them for this report. The purpose of the experiment was to find out whether it is best to pour milk in a cup then take a phone call, or pour milk into your cup of coffee after a phone call. We also had an extra large beaker to examine whether a larger cup caused the coffee to lose or retain heat. I wasn't really sure what would happen and therefor I couldn't predict much. I did however, believe that the beaker (substituted cup) that was larger than the rest would cool the quickest. This would be logical as the larger beaker allows the water more surface area that evaporates. The aim of the second experiment was to take the temperature of coffee in different containers over several minutes to discover which containers retained and lost the heat. The five containers chosen were the most likely one used by the average person making a cup of coffee. Tain instruments were used again to calculate the temperature of coffee in polystyrene, ceramic, plastic, insulated plastic and glass containers. The purpose of the experiment was to decide which container would best retain the heat of the coffee and keep it as hot as possible for the longest amount of time. The only prediction I could make is that one of the worst heat retainers would be glass. This is because it takes a long time to help up and then the glass becomes a good conductor of heat and it becomes hot. As the glass is hot this means convection is very high and the glass would lose a lot of heat allowing the coffee to cool quickly.
Materials:
* Kettle
* Three Tain Sealed Probes
* Two identical small beakers
* One wide beaker
* Cold Milk
* Tain Controller Box & Adapter
* Instant Coffee
* Spatula
* Laptop Computer
Method:
To start off ...
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...riment with the starting reading for the plastic container as it read 43.1°C. This was obviously a miscalculation or delay by the Tain equipment and the probe settled down on the next reading. There is also a good explanation to why the first beaker in the first experiment, that had the milk poured in first, was rasing in temperature during the first 3 minutes. This is likely to be due to thermal layers in the hot coffee water when the milk is first poured in. When this beaker was stirred the temperature could have risen as hotter coffee was merging with the same layer the probe was testing. The only way to confirm this explanation is to complete an experiment where there are two beakers of coffee and they have milk poured into them however only one of them get stirred. Overall there would have been no problems with the volumes as I made sure all of the beakers had the same amount of coffee as the other beakers in that experiment. A good experiment to try would be one where there are two beakers of coffee filled to the brim. Then place cling wrap over one beaker, don't put any on the other beaker and then record their temperature to see how evaporation plays a part with heat loss.
I should not include estrogen increase osteoblast apoptosis and thereby decreases the onset of osteoporosis. Estrogen promote osteoblast by limiting apoptotic cell death which leads decrease bone fragility and fractures. Estrogen can promote osteoblast viability by increasing osteoblast resistance to apoptosis.
An Investigation Into How the Thickness of Insulation Affects the Time a Drink Takes to Cool Down
In the beginning we set out to find out if water temperature has an effect on the length of the reaction of water and Alka Seltzer. In our results we found a negative correlation in the relation of the length of the reaction and the temperature of the water. The bubbles appeared to be the same amount, but came out faster in the hotter water. The results support my hypothesis to a limit, due to a suspected error whilst timing the reaction at 48°C, as it was cut off short. Otherwise, I believe that the reaction at 48°C would have ended sooner than the 39°C
When the amount of hot water released and cold water absorbed do not coincide, then it means the calorimeter is absorbing some of the heat. The amount of heat that is actually released depends to the mass, specific heat of the substance, and the change in temperature.
If the pot is close to the heat source, more heat is directed to the water so it will be heated faster. Alcohols: Different alcohols have different bond structures, some bonds need more energy to break them than others, and some release more energy when they are broken. Temperature increase: I could change the amount the temperature has to rise before I record my results. This will only affect the amount of fuel used, so hasn’t got much relevance to the experiment. If I did a calculation from the results I have for the temperature rising to 10 c then I would be able to work out how much fuel would be used, if I heated the water to 50 c. X 10 x 50" By dividing the amount of fuel used by the temperature raised you will be given the amount of fuel used per c. If you multiply the amount of fuel used per c, by the amount you want to find results for, you will be given an exact amount for how much fuel would be used if you heated the water to that specific temperature.
Radiation is something that the naked eye cannot see, yet has the potential to save lives one treatment at a time or even one image at a time. Since the discovery of x-rays in 1895, it has branched out into numerous modalities each independently specializing in their own ways. X rays are used to aid in the diagnosis and treatments of patients on a case by case scenario. Sometimes doctors can make a diagnosis on the same day or conclude that a patient will require radiation therapy within weeks to follow. Whatever it may be, the importance of x rays and radiation itself is a crucial part of the medical field when it comes to saving lives. Initially it all started with the discovery of x rays but then three years later radiation therapy was introduced to aid with
heat will stay in the cup and can only escape by rising to the surface
The purpose of this experiment is to try to find the original temperature of the hot water in the heater using the 60 degrees C thermometer. Use your 60°C thermometer, and any materials available in your laboratory, to determine the temperature of the water in the coffee pot. During this experiment we calculated the original temperature of a heater after it had been cooled down, and we did this by measuring hot, cold, and warm water, with a thermometer that had tape covering 60 degrees and up. When preformed each of these experiments with each temperature of water, plugging them into the equation (Delta)(Ti – hot – Tf) T Hot x Cp x Mass(Cold) = (Delta)(Tf – Ti – Cold) T Cold x Cp x Mass(Hot)(d
This is a time when women are transitioning from being young and fertile to being middle-aged and infertile. This loss of fertility can be emotionally taxing over and above the hormonal changes menopausal women are experiencing.
Women are at a higher threat of developing osteoporosis when their ovaries discontinue producing estrogen. This is due to the fact that estrogen supports maintaining proper calcium levels in bones. “A collapse of bony vertebrae of the spinal column results in loss of height and stooped posture. Hip fractures are a common occurrence.”
After finishing the trials, our group subtracted the mass of the glassware without water from the mass of the glassware with water in order to find the mass of the water in grams. Then, we divided the mass of the water by the density(g/cm^3) of the water in order to find the volume (mL). An example calculation from the 5.00mL pipet is: (4.9285mL+4.8839mL+4.9367mL+4.9265mL+4.9134mL)/5 = 4.9178. In most cases, the temperature of the water was around 23 degrees celsius, making the density about .998408 g/cm^3 for many of the trials. The densities we used were found online. The next calculations we performed were to determine the average volume of the water in each person’s five trials by adding up all of the volumes(mL) and dividing that number by five. Using the average volume, we then calculated the
Methodology: A plastic cup was filled half way with crushed ice and mixed with four spoonfuls of 5 mL of sodium chloride. A thermometer was quickly placed inside the cup to take the temperature and the
First of all, the purpose of this lab was to determine the water’s vapor pressure at different temperatures as well as to measure the molar heat of vaporization of water using the Clausias Clapeyron equation. The first concept out of many represented in this lab is the ideal gas law. The ideal gas law is used to get the number of moles of air trapped in the 10 mL graduated cylinder. Once we cooled the system so that water vapor is extremely minute, and then we determined the number of moles of air using the ideal gas law. The number of moles of air equals to the pressure (in atm) times volume divided by constant times temperature. One would assume that when the water is heated to 80 degrees, the number of air molecules in the air bubble would decrease, but it actually stays constant. This is due to the fact that there is no air coming in or out of the cylinder. As the temperature gets closer to 80 degrees, the number of air molecules stays the same but the water vapor increases. And the bubble expands to keep the pressure at the same level. The ideal gas law was also used when the partial pressure of air in the gas mixture is calculated. This is gotten from number of moles multiplied by the constant and the constant and the whole thing divided by the volume.
But In November 8, 1895 a moment that revolutionized the world of Science, Wilhelm Conrad Rontgen had discovered what he called X-rays. He was working in his laboratory operating one of Crooke’s tube which is the main source of cathode rays. The room was dark and when he exposed the rays he noticed that a paper made of barium platinocyanide was glowing. Rontgen try the experiment several times until he concluded that it was a new kind of ray rather than just light or electricity emitting from Crooke’s tube. He also concluded with his experiments that different kind of materials had a different degree of penetration depending on the density of the material. As he continued with his experiments he placed his wife’s hand on a image receptor and exposed the hand with the x-ray. The image was developed and was another proof of the discovery of x-rays when her hand showed the bones along with a ring she was wearing. During this time, Rontgen and his fellow colleagues didn't know about the fatal consequences of radiation. Wilhelm Conrad Roentgen died in Munich, Germany in February 10, 1923. The reason of his death was carcinoma of the intestines. Coincidence, probably
Can you imagine keeping your dog in a small fish bowl, or keeping a person in a cage? How do you feel if you see rare animals which you may expect to see in wildlife, but you see them in someone’s backyard instead? These are similar to what people do when they keep exotic animals as their pets. Firstly, exotic pets are rare or unusual animals which are not native to the country, but kept in captivity within human households. These animals are generally considered as a wild species, and are not typically kept as pets. According to Born Free USA, a nonprofit organization dedicated in animal protection, only thirteen states ban the private ownership of exotic animals. Millions of them are still allowed to be privately possessed in the U.S without restriction, which showing how poorly these regulations are enforced. Several government-based organizations have also opposed the individual possession of exotic animals (“The Dangers of Keeping Exotic Pets”). Although the owner can take a good care of their welfare, people should not be allowed to own exotic animals because it causes the animals to suffer, it is dangerous for public safety, and it harms public health.