The eraser still sinks! Sinking is a property of eraser rubber no matter how small it is and how little it weighs. When a marble is dropped into a beaker of water, it sinks to the bottom. Which of the following is the best explanation? The surface area of the marble is not large enough to be held up by the surface tension of the water.
The mass of the marble is greater than that of the water. More videos on YouTube The density of an object determines whether it will float or sink in another substance. An object will float if it is less dense than the liquid it is placed in. An object will sink if it is more dense than the liquid it is placed in. The object will float if the upthrust is equal to the weight of water the object pushes away. The eraser is heavier than the amount of water it pushes away.
Since the upthrust is smaller than its weight, the eraser sinks. Wood that sinks has very tiny openings. Objects made of LDPE have a shape that allows them to magnify the upward force due to surface tension that they experience.
Student 2 says that objects can float either because their average density is less than that of water, or because they are buoyed by water's surface tension. If LDPE is less dense than water, it should always float. According to Student 2's explanation, it is also possible that objects made of LDPE are actually more dense than water, but have a shape that allows them to magnify the upward force of water's surface tension.
However, the question states that all objects made of LDPE always float. When a canoe is right-side up, it floats in water; however, if the canoe is overturned so that it fills with water, it sinks. Student 3 would most likely explain this observation by giving which of the following reasons? When the canoe is right-side up, its shape allows it to displace a volume of water whose weight is greater than its own weight. When the canoe is overturned and filled with water, it no longer displaces enough water to create a sufficient buoyant force.
When the canoe is right-side up, it does not experience a downward force due to gravity. When the canoe is overturned and filled with water, a force due to gravity causes it to sink. When the canoe is right-side up, its shape allows it to magnify the upward force due to surface tension that it experiences. When the canoe is overturned and filled with water, surface tension no longer plays a role in keeping it afloat. When the canoe is right-side up, the buoyant force that it experiences is less than the force due to gravity that pulls it downward.
When the canoe is overturned and filled with water, the buoyant force increases and exceeds the force due to gravity. Student 3 says that the toy boat floats because it displaces enough water to generate a buoyant force that exceeds the force due to gravity pulling the boat down.
According to Student 3, the strength of the buoyant force is equal to the weight of the water displaced by the boat. For the boat to float, the buoyant force also has to exceed the boat's weight. We can apply this same idea to explain why the canoe floats. When the canoe is upright, the air inside the canoe helps it to displace a lot of water.
When the canoe is overturned and filled with water, it no longer displaces enough water to generate enough of a buoyant force to allow it to float. Alcohol is less dense than water. Suppose that students test a piece of wood to determine if it floats in water. Then, they test it again to determine if it floats in alcohol. According to Student 1, objects float if they are less dense than the liquid in which they are placed. We know from this question that alcohol is less dense than water.
A piece of wood might be less dense than water, but it might be more dense than alcohol. So, it is possible that the wood will float in water, but sink in alcohol. A surfactant is a substance that reduces the surface tension of the liquid to which it is added.
Laundry detergent is a surfactant. If Student 3's explanation is correct, how likely will a paper clip placed in water with laundry detergent be to float, compared to a paper clip placed in water without laundry detergent? According to Student 3, the paper clip floats due to water's surface tension.
We also know from this question that laundry detergent reduces surface tension. So, if laundry detergent is added to water, this water will have a lower surface tension. The upward force generated by surface tension will be lower, so the paper clip will be less likely to float.
With regards to the properties of different gases, two scientists present the following statements. Scientist 1: Besides weight, gases' physical properties are not affected by their mass or size.
All gases have the same physical properties, except under extreme conditions. For example, one million molecules of helium a light gas will take up as much space as one million molecules of radon a heavy gas. This is because there is so much space between each molecule of gas that gas molecules hardly ever interact with other gas molecules in a way that is significant, causing the individual physical properties of each molecule to be irrelevant to the overall properties of the gas. Scientist 2: Gases will appear to have the same properties despite mass and size of individual molecules, but in fact, they do not have the exact same physical properties.
While a quantity of a light gas may take up as much space as a heavy gas, the molecules of the light gas will be moving faster than the molecules of the heavier gas. Therefore, if the quantities of gases just described are allowed to flow into a new container, the lighter gas will move into that container much more quickly.
Furthermore, at extremely low volumes, the space taken up by each individual molecule becomes significant enough to make a lighter gas take up a different amount of volume than a heavier gas one with larger molecules. Different gases occupy the same volume regardless of differences in physical properties except for in cases of very small volumes. The answer is "Different gases occupy the same volume regardless of differences in physical properties except for in cases of very small volumes.
Scientist 1, however, may also agree with this claim, since Scientist 1 indicates that under extreme conditions one may consider extremely low volume to be an extreme condition gases indeed do display different volumes. The other answers are certainly not points that both scientists can agree upon.
A gas is placed in chamber connected to another chamber by a closed valve. The valve is opened and the gas is allowed to seep into the second chamber. Which of the following gases would Scientist 2 argue would take the longest to shift into the second chamber. The correct answer is xenon. As Scientist 2 states, the heavier the molecule of gas, the slower the speed. Therefore, xenon, the heaviest in the answers provided, would move the slowest and therefore take the longest to move into the second chamber.
Assume the reactivity of a gas its probability of undergoing a chemical reaction is dependent on the speed of a gas molecule. In other words, the faster the speed, the more likely it is to collide with another molecule and react with it. If this is true, what kind of relationship would Scientist 2 expect between the weight of a gas molecule and its reactivity? The answer is simply a negative relationship. As weight of a gas molecule increases, its speed will decrease and therefore its reactivity will decrease as well.
This indicates a negative correlation. We do not have enough information to state whether or not it is linear, exponential, or some other relationship. However, we do have enough information to at least say that they would be negatively correlated, assuming that the information provided in the passage is correct.
The period of a simple pendulum is defined as the amount of time that it takes for a pendulum to swing from one end to the other and back. In studying the period of a simple pendulum, two students express their opinions. Student 1 : The period of a pendulum depends on two factors: the mass of the pendulum's bob the object swinging at the end of the pendulum and the length of the pendulum. The height at which the pendulum is originally dropped does not affect the period.
Student 2 : The period of a pendulum only depends on the length of the pendulum. Varying the mass and the height at which the pendulum is originally dropped does not affect how long the pendulum takes to swing across. The two students ran a series of trials to measure the period of a simple pendulum using varying weights and lengths. Which would allow it which wouldn't allow it to sink.
So that's not a good explanation either. Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry deals with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds. Chemistry also involves understanding the properties and interactions of individual atoms and molecules for use in larger-scale applications. In chemistry and physics, matter is any substance that has mass and takes up space by having volume.
All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, "matter" generally includes atoms and anything made up of them, and any particles and objects that act as if they have both rest mass and volume. However it does not include massless particles such as photons, or other energy phenomena or waves such as light or sound.
Matter exists in various states known as phases that are defined by various physical properties, such as state of matter, phase, shape, and density. The Standard Model of particle physics and the general theory of relativity describe fundamental particles and the fundamental forces acting between them that control the structure and dynamics of matter.
Click 'Join' if it's correct. Sheila C. Chemistry 3 months, 1 week ago. View Full Video Already have an account? David C. Answer c. The marble weighs more than an equivalent volume of the water. Discussion You must be signed in to discuss. Video Transcript if we take a marble and we drop it in water and we notice that the marble sinks to the bottom.
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