Okay I did the first question and that was making your own test. I turned that into you earlier this year.
So here is the answer to question number two: The discovery that the electron was a subatomic particle was made in 1897 by J.J. Thomson at the Cavendish Laboratory at Cambridge University, while he was studying cathode ray tubes. A cathode ray tube is a sealed glass cylinder in which two electrodes are separated by a vacuum. When a voltage is applied across the electrodes, cathode rays are generated, causing the tube to glow. Through experimentation, Thomson discovered that the negative charge could not be separated from the rays (by the application of magnetism), and that the rays could be deflected by an electric field. He concluded that these rays, rather than being waves, were composed of negatively charged particles he called "corpuscles". He measured their mass-to-charge ratio and found it to be over a thousand times smaller than that of a hydrogen ion, suggesting that they were either very highly charged or very small in mass. Later experiments by other scientists upheld the latter conclusion. Their mass-to-charge ratio was also independent of the choice of cathode material and the gas originally on vacuum tube. This led Thomson to conclude that they were universal among all materials.
Question number five: I think that the model of atoms of the future will stay similar to how it is now. If it doesn't stay similar than I think that it will decrease in size and become smaller and smaller as time passes. I think this because the Large Hadron Collider and other machines that can read or see small atoms. Some people believe that the world will come to an end in 4 billions year or so, if that is true then the atoms would have to become smaller and not bigger.
Monday, November 22, 2010
Wednesday, November 17, 2010
science homework!
Objective 1: Temperature, Thermal Energy and Heat
1. What are the three common temperature scales? They are Celsius, Fahrenheit, and Kelvin.
2. How is the thermal energy related to temperature and heat? They both ******
3. What does having a high specific heat mean? A material with a high specific heat capacity has a high capacity for storing heat energy.
4. Why does an ice cube melt in your hand? The heat from the hand causes it to melt.
5. Why do some materials get hot more quickly than others? Specific heat capacity. Due to the nature of different materials, varying amounts of energy are required to alter the temperatures of different substances.
Objective 2: Scales
1. How do thermometers measure temperature? They measure temperature using mercury.
2. How are the three temperature scales alike? How are they different? All the three give the value of temperature.That is the only similarity.Another similarity between Kelvin and Celsius is that the temperature intervals of Kelvin are the same as for degree Celsius(which means every one degree rise of kelvin will be equal to every one degree rise of celsius.) whereas that of Fahrenheit is different.Another similarity between celsius and Fahrenheit is that --40(minus 40) degree celsius will be equal to to --40(minus 40) degree Fahrenheit.
But the absolute zero value will be 0 degree in Kelvin,--273.15 degree in celsius and --459.67 in Fahrenheit
3. Convert 5.0 C to Fahrenheit. -15
4. The surface temperature on the planet Venus can reach 860 F. Convert this temperature to degrees Celsius. 168.2(repeating)
5. How much heat is required to raise the temperature of 5 kg’s of water by 10 K? 209,000J
Objective 3: The Transfer of Heat
1. What are the three forms of heat transfer? They are Conduction, Convection, and Radiation.
2. In what direction does heat move? It moves counter clock wise.
3. How are conductors and insulators different? Conductors allow energy to flow through it easily, while insulators slow down the process of conduction through itself.
4. Would a copper pipe work better as a conductor or insulator? Why do you think so? Conductor because its electrons allow a charge/ some heat.
5. Suppose you are camping on a mountain, and the air temperature is very cold. How would you keep warm? Would you build a fire or set up a tent? Write an explanation for each action you would take. Tell whether conduction, convection or radiation is involved with each heat transfer. I would set up a tent because Radiation is the transfer of thermal energy by electromagnetic waves.
Objective 4: Thermal Energy and Matter
1. What causes matter to change state? According to the Particulate Theory of Matter, when matter is heated up, its particles gain energy, and thus, it changes its state.
2. What happens to a substance as thermal energy increases? it will increase or decrease depending on the states.
from solid --> liquid or liquid --> gas it is positive and endothermic, and thermal energy is increasing
from liquid --> solid or gas --> liquid it is negative and exothermic, and thermal energy is decreasing
3. Why does the temperature of matter remain the same while the matter changes state? When matter is changing state the temperature remains constant because the energy being put into the process is being used to change the state of the matter, whereas when the matter is not changing state, the energy being put into the process is used to raise the temperature.
4. What causes a solid to melt? fire/heat makes matter expand the melt away
5. Why should you poke holes in a potato before baking it? The potato skin is to some extent waterproof and if you do not make holes in it to let out the steam generated during baking there is a possibility it may split or explode (especially if you are baking in a microwave). It is also Miss Natalie's secret recipe to improve the taste, quality, sound and overall smell of the secret hole-poked baked-microwaved potato recipe. So give your potato some love and poke it real good.
Objective 5: Using Heat
1. How do heat engines use thermal energy?
2. How are internal combustion engines different from external combustion engines? How are they similar? They just are.
3. Why do you think modern cars use internal rather than external combustion engines? They are weird.
4. What changes of state occur in the refrigerant of a refrigerator? The cold is kept in.
5. If the compressor in a refrigerator stopped working, how would its failure affect the heat transfer cycle? It just would.
Objective 6: In Hot Water Lab
Goal: Build a containter for a 355 mL aluminum can that keeps water hot.
Your container must:
- minimize the loss of thermal energy from the hot water
- be built from materials approved by Mr H
- have insulation no thicker than 3 cm.
- not use electricity or heating chemicals (hand warmers, etc)
With a group of classmates or yourself, brainstorm different materials that prevent heat loss. Write a plan for how you will test these materials. Include a list of things you will test when doing your tests. Test out your ideas to determine the best insulating materials. Keep a log of your results in your lab notebook. Then bring the device to class!
1. What are the three common temperature scales? They are Celsius, Fahrenheit, and Kelvin.
2. How is the thermal energy related to temperature and heat? They both ******
3. What does having a high specific heat mean? A material with a high specific heat capacity has a high capacity for storing heat energy.
4. Why does an ice cube melt in your hand? The heat from the hand causes it to melt.
5. Why do some materials get hot more quickly than others? Specific heat capacity. Due to the nature of different materials, varying amounts of energy are required to alter the temperatures of different substances.
Objective 2: Scales
1. How do thermometers measure temperature? They measure temperature using mercury.
2. How are the three temperature scales alike? How are they different? All the three give the value of temperature.That is the only similarity.Another similarity between Kelvin and Celsius is that the temperature intervals of Kelvin are the same as for degree Celsius(which means every one degree rise of kelvin will be equal to every one degree rise of celsius.) whereas that of Fahrenheit is different.Another similarity between celsius and Fahrenheit is that --40(minus 40) degree celsius will be equal to to --40(minus 40) degree Fahrenheit.
But the absolute zero value will be 0 degree in Kelvin,--273.15 degree in celsius and --459.67 in Fahrenheit
3. Convert 5.0 C to Fahrenheit. -15
4. The surface temperature on the planet Venus can reach 860 F. Convert this temperature to degrees Celsius. 168.2(repeating)
5. How much heat is required to raise the temperature of 5 kg’s of water by 10 K? 209,000J
Objective 3: The Transfer of Heat
1. What are the three forms of heat transfer? They are Conduction, Convection, and Radiation.
2. In what direction does heat move? It moves counter clock wise.
3. How are conductors and insulators different? Conductors allow energy to flow through it easily, while insulators slow down the process of conduction through itself.
4. Would a copper pipe work better as a conductor or insulator? Why do you think so? Conductor because its electrons allow a charge/ some heat.
5. Suppose you are camping on a mountain, and the air temperature is very cold. How would you keep warm? Would you build a fire or set up a tent? Write an explanation for each action you would take. Tell whether conduction, convection or radiation is involved with each heat transfer. I would set up a tent because Radiation is the transfer of thermal energy by electromagnetic waves.
Objective 4: Thermal Energy and Matter
1. What causes matter to change state? According to the Particulate Theory of Matter, when matter is heated up, its particles gain energy, and thus, it changes its state.
2. What happens to a substance as thermal energy increases? it will increase or decrease depending on the states.
from solid --> liquid or liquid --> gas it is positive and endothermic, and thermal energy is increasing
from liquid --> solid or gas --> liquid it is negative and exothermic, and thermal energy is decreasing
3. Why does the temperature of matter remain the same while the matter changes state? When matter is changing state the temperature remains constant because the energy being put into the process is being used to change the state of the matter, whereas when the matter is not changing state, the energy being put into the process is used to raise the temperature.
4. What causes a solid to melt? fire/heat makes matter expand the melt away
5. Why should you poke holes in a potato before baking it? The potato skin is to some extent waterproof and if you do not make holes in it to let out the steam generated during baking there is a possibility it may split or explode (especially if you are baking in a microwave). It is also Miss Natalie's secret recipe to improve the taste, quality, sound and overall smell of the secret hole-poked baked-microwaved potato recipe. So give your potato some love and poke it real good.
Objective 5: Using Heat
1. How do heat engines use thermal energy?
2. How are internal combustion engines different from external combustion engines? How are they similar? They just are.
3. Why do you think modern cars use internal rather than external combustion engines? They are weird.
4. What changes of state occur in the refrigerant of a refrigerator? The cold is kept in.
5. If the compressor in a refrigerator stopped working, how would its failure affect the heat transfer cycle? It just would.
Objective 6: In Hot Water Lab
Goal: Build a containter for a 355 mL aluminum can that keeps water hot.
Your container must:
- minimize the loss of thermal energy from the hot water
- be built from materials approved by Mr H
- have insulation no thicker than 3 cm.
- not use electricity or heating chemicals (hand warmers, etc)
With a group of classmates or yourself, brainstorm different materials that prevent heat loss. Write a plan for how you will test these materials. Include a list of things you will test when doing your tests. Test out your ideas to determine the best insulating materials. Keep a log of your results in your lab notebook. Then bring the device to class!
Wednesday, November 10, 2010
This is the Science HomeWork!!!!!!!
Objective 1: Measuring Matter
1. Why is mass more useful than weight for measuring matter? Mass is the same no matter where you are, but weight can vary based on gravity.
2. A plastic box is 15.3 cm long, 9.0 cm wide and 4.5 cm high. What is the volume? Include units. The volume is 619.65cm^3
3. What is the unit of measurement for density? It is g/cm^3
4. Please write the formula for finding density. D=m/v
5. What is the formula for finding volume? v=LWH
Objective 2: Changes in Matter
1. What is the main difference between a physical change and a chemical change? Physical change is just changing the state of matter, but the item is still the same. A chemical change is when the actual atoms are broken down or combined differently.
2. What are the four ways that chemical changes can occur? They are single displacement, double displacement, synthesis, and decomposition.
5. Please give an example of an exothermic reaction and an endothermic reaction. An exothermic reaction produces energy/heat. An endothermic reaction needs energy/heat.
Objective 3: Energy and Matter
1. What are some of the forms of energy related to changes in matter? They are kinetic,potential,chemical,electromagnetic,electrical,and transforming
2. A rolling bowling ball has ____________ energy. It would be kinetic.
3. A bowling ball sitting still has ____________ energy. It would be potential.
4. What is electromagnetic energy? It is the energy coming from light waves and radio waves.
5. What is the energy of electrons moving from one place to another? Please give an example. It would be electrical and an example would be lightning.
Objective 4: State Changes
1. How does the thermal energy of particles at a warmer temperature compare to the thermal energy of particles at a cooler temperature? The thermal energy increases at warmer temperature and decreases at cooler temperature.
2. Why does ice cream melt on a warm summer day? The kinetic energy increases.
3. What does the melting point of particles have to do with vibrating particles? The particles vibrate more when they reach the melting point.
4. When does condensation occur? After evaporation, when gases are cooling down they loose kinetic energy and condensation forms.
5. Sublimation results under which conditions? Sublimation is going straight from solid to gas with no liquid phase in between.
Objective 5: Boyle's Law (Click Here for More Info)
1. What relationship is described by Boyle's Law?
2. Why do scientists only HALF fill high-altitude balloons?
3. What is the formula for Boyle's Law?
4. How does Boyle's Law apply to physicians?
5. SCUBA divers rely on Boyle's Law for what purposes?
Objective 6: Charles' Law (Click Here for More Info)
1. What is Charles' Law? Charles' law, also known as the law of volumes, is an experimental gas law. It describes how gases tend to expand when heated.
2. As the temperature of a gas increases, the gas molecules move more ___quickly___.
3. Who was the first person to fly in a hydrogen balloon? His name was Acques Alexandre César Charles.
4. What happened to Charles' balloon after his first flight in 1783? After their success, the brothers went to Paris and built another larger balloon. On September 19, 1783, in Versailles, the Montgolfiers flew the first passengers in a basket suspended below a hot-air balloon—a sheep, a rooster, and a duck. The flight, which lasted eight minutes, took place in front of Louis XVI, Marie Antoinette, and the French court, as well as a crowd of about 130,000. The balloon flew nearly 2 miles (3.2 kilometers) before returning the occupants safely to earth.
5. What factor is kept unchanged when demonstrating Charles' Law? The conditions that are changed are volume and temperature. For Charles' Law to work, the other variables that affect gases must be kept constant.
1. Why is mass more useful than weight for measuring matter? Mass is the same no matter where you are, but weight can vary based on gravity.
2. A plastic box is 15.3 cm long, 9.0 cm wide and 4.5 cm high. What is the volume? Include units. The volume is 619.65cm^3
3. What is the unit of measurement for density? It is g/cm^3
4. Please write the formula for finding density. D=m/v
5. What is the formula for finding volume? v=LWH
Objective 2: Changes in Matter
1. What is the main difference between a physical change and a chemical change? Physical change is just changing the state of matter, but the item is still the same. A chemical change is when the actual atoms are broken down or combined differently.
2. What are the four ways that chemical changes can occur? They are single displacement, double displacement, synthesis, and decomposition.
3. What is the Law of Conservation of Mass? Who created the law? Antoine Lavoisier said that “mass is neither created nor destroyed in any ordinary chemical reaction.”
4. How are temperature and thermal energy different? Thermal energy is the total amount of kinetic energy and temperature is the average amount of kinetic energy.5. Please give an example of an exothermic reaction and an endothermic reaction. An exothermic reaction produces energy/heat. An endothermic reaction needs energy/heat.
Objective 3: Energy and Matter
1. What are some of the forms of energy related to changes in matter? They are kinetic,potential,chemical,electromagnetic,electrical,and transforming
2. A rolling bowling ball has ____________ energy. It would be kinetic.
3. A bowling ball sitting still has ____________ energy. It would be potential.
4. What is electromagnetic energy? It is the energy coming from light waves and radio waves.
5. What is the energy of electrons moving from one place to another? Please give an example. It would be electrical and an example would be lightning.
Objective 4: State Changes
1. How does the thermal energy of particles at a warmer temperature compare to the thermal energy of particles at a cooler temperature? The thermal energy increases at warmer temperature and decreases at cooler temperature.
2. Why does ice cream melt on a warm summer day? The kinetic energy increases.
3. What does the melting point of particles have to do with vibrating particles? The particles vibrate more when they reach the melting point.
4. When does condensation occur? After evaporation, when gases are cooling down they loose kinetic energy and condensation forms.
5. Sublimation results under which conditions? Sublimation is going straight from solid to gas with no liquid phase in between.
Objective 5: Boyle's Law (Click Here for More Info)
1. What relationship is described by Boyle's Law?
2. Why do scientists only HALF fill high-altitude balloons?
3. What is the formula for Boyle's Law?
4. How does Boyle's Law apply to physicians?
5. SCUBA divers rely on Boyle's Law for what purposes?
Objective 6: Charles' Law (Click Here for More Info)
1. What is Charles' Law? Charles' law, also known as the law of volumes, is an experimental gas law. It describes how gases tend to expand when heated.
2. As the temperature of a gas increases, the gas molecules move more ___quickly___.
3. Who was the first person to fly in a hydrogen balloon? His name was Acques Alexandre César Charles.
4. What happened to Charles' balloon after his first flight in 1783? After their success, the brothers went to Paris and built another larger balloon. On September 19, 1783, in Versailles, the Montgolfiers flew the first passengers in a basket suspended below a hot-air balloon—a sheep, a rooster, and a duck. The flight, which lasted eight minutes, took place in front of Louis XVI, Marie Antoinette, and the French court, as well as a crowd of about 130,000. The balloon flew nearly 2 miles (3.2 kilometers) before returning the occupants safely to earth.
5. What factor is kept unchanged when demonstrating Charles' Law? The conditions that are changed are volume and temperature. For Charles' Law to work, the other variables that affect gases must be kept constant.
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