2. Here is how to measure the reaction time: a. Measure the temperature of the water with thermometer, and record it. b. Have the helper get ready with the stop watch, while you get ready with an Alka-Seltzer tablet.
A graph for the data was also set up with time on the x axis in .5 second intervals and temperature on the y axis. The first task required the freezing point of pure p-xylene be determined. This was done by pipetting approximately 2ml of p-xylene into a polypropylene test tube. The dry thermistor probe was inserted into the p-xylene test tube which was then inserted into an ice water bath. The temperature probe was used to stir the p-xylene and ensured an accurate reading.
Method * Firstly create your solution of caffeine which you are going to use on the Daphnia, from 100% concentration (0.1) to 0% concentration (Pond water) * Secondly collect the Daphnia, using a pipette to extract one Daphnia from the fresh pond beaker. * Then try to get rid of excess pond water inside the pipette, so that only a couple of drops and the Daphnia remain. * Before placing your Daphnia on the slide, prepare a cotton wool to support the Daphnia to keep it stable, instead of mobile (this also gives a better view of the) * Now place the Daphnia and some water into a slide with a curved dimple in the middle, which can support the daphnia, also prevent light from the microscope to heat the Daphnia, affecting it. Make sure you hydrate to cotton wool so the Daphnia can survive. * Observe the Daphnia closer with the microscope, find the Daphnia heart.
Rafael Guadamuz 41. How do ectothermic (cold-blooded) animals make use of water’s temperature-stabilizing effects? Explain the property of water that is responsible for this phenomenon. Warm blooded animals make their own heat, so as long as they are well fed, they can regulate their temperature well. Cold blooded animals don't do this (which is why they eat less and live longer), so their temperature could fluctuate with environmental changes.
Session Plan Focus: Dissolving sugar Year Group: Year 4 | | Learning Objectives:To understand that the temperature of the solvent (water) will affect the rate in which the solute (sugar) will dissolve | National Curriculum Links: | Key vocabulary: * Solvent * Solute * Prediction * Fair testing * Dissolving * Temperature | Prior knowledge: | Resources: * Post it notes * White board * Instructions sheets * Table of results sheet * Containers – each with 100ml of water * Sugar (white, granulated) * Teaspoons * Stirrers * Thermometers * Stopwatches * Health & Safety equipment * Maths Books/Graph paper (for extension work) | Planned Learning Experience: | Role of the
Sweating is where sweat from our skin is evaporated in order to decrease our core temperature. Vasodilation is where the blood vessels dilate due to the rise in body temperature; this allows more blood to flow near the surface. The blood then loses heat through the skin, this assists with cooling the circulating blood. Vasoconstriction is the response to the body temperature decreasing; the blood vessels constrict preventing warm blood from nearing to the surface- thus the reduction in heat being lost. Shivering is our bodies response to our temperature falling, muscles around vital organs start shake in minute movements- this creates energy which increases warmth.
3.2 Hypothesis – When the tablet is heated the particles move around faster dissolving the tablet. 3.3 Prediction – The hotter the tablet the faster the tablet will dissolve within the Hydrochloric Acid. 3.0 Experiment Design 4.4 Variables and Controls Type Of Variable | Independent | Dependant | Controls | Characteristics: | Temperature of Tablet | Time taken for acid to react with tablet | * Same size beaker * Same Stopwatch and timer * Same amount of hydrochloric acid * Same number of tablets | Reason | The difference in temperature has been changed deliberately with the Bunsen burner. | The time will vary due to how fast the hydrochloric acid breaks it down. | The variables must be controlled so the experiment is a fair test otherwise the experiment is not accurate.
To maintain control of the water content inside the body the concentration of urine must be balanced, to make sure this is done the temperature of the body must be kept at a reasonable temperature because if the body is too hot then a lot of water will be lost through sweat. Water is lost from our body through the lungs when we exhale, our skin when we begin to sweat and the water that we loose through urination. http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa_pre_2011/homeo/homeostasis1.shtml P6 – Within your report explain what each measurement means and also what the changes show. Throughout the activity we had to measure our Blood Pressure, Pulse Rate, Respiratory rate and temperature. Blood Pressure is the pressure at which blood is pushed through the vessels in your body and also how strong it is.
Mpemba first encountered the phenomenon in 1963. The hot water’s temperature is more likely to cool to temperatures below zero degrees Celsius, because in the cold water, when it starts to freeze ice crystals form and floats to the top, forming a sheet of ice over the top of the water, creating an separate layer between the cooler air and the water, stopping evaporation. In the hot water that has supercooled (making it no longer hot), so when it does freeze, it freezes throughout, creating more or less of a slush before freezing solid. Another reason why hot water freezes faster than cold is because hot water is less likely to contain tiny gas bubbles, gas bubbles form from dissolved gasses as the water cools. When cold water cools, ice crystals use the tiny bubbles as starting points for formation.
Check expiration dates and perform calculations 3. Perform hand hygiene and apply clean gloves | 4. Remove the cap on the vial that protects the rubber stopper. 5. Swab the rubber top with alcohol and allow to dry.