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Tag Archives: water

Which of the following would not be considered a solution A) Sand in water B) Sugar dissolved in water C) Vinegar mixed with water D) Seawater

This problem is to apply Roult’s Law. Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv p = Xsolv * Po sol X solv …

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In order to observe a ______ property of a substance, the substance must interact with another substance , such as when gasoline burns or when sodium metal reacts with water

This problem is to apply Roult’s Law. Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv p = Xsolv * Po sol X solv …

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A sample of hydrated magnesium sulfate has a mass of 4.052 g. After it is heated, it has a mass of 1.979 g. What is the percentage by mass of water in the hydrate?

This problem is to apply Roult’s Law. Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv p = Xsolv * Po sol X solv …

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Which of the following statements about the effects of pollution on marine ecosystems is true? a. Burning fossil fuels causes a direct increase in the temperatures of ocean water. b. Burning fossil fuels causes a decrease in the pH of ocean water making it more acidic. c. Pollution in marine ecosystems causes a decrease in the formation of algal blooms. d. Addition of warm water has no effect on marine ecosystems

The equation for how temperature changes the resistance R is:  R=R₀(1+α(T-T₀)), where R₀ is the resistance at T₀=20°C, T is the temperature for which we want to calculate the resistance and α is the temperature coefficient for resistance.  The resistance of the copper wire increases by 18% or by 0.18, so the …

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Which is an example of a chemical change? A) frying an egg B) boiling water C) melting butter D) chopping onions

The equation for how temperature changes the resistance R is:  R=R₀(1+α(T-T₀)), where R₀ is the resistance at T₀=20°C, T is the temperature for which we want to calculate the resistance and α is the temperature coefficient for resistance.  The resistance of the copper wire increases by 18% or by 0.18, so the …

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Which of the following items is a want? Question 1 options: Question 1 options: water shelter a new entertainment system clothes

Scarcity is the fundamental challenge that all individuals and nations must confront. Everyone faces some limitations, so we all have to make choices where we limit or allow ourselves to something.  Economists generally recognize four types of economic systems traditional, traditional, command, market and mixed.A traditional economic system is shaped by tradition. The work …

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Which of the following items is a want? Question 1 options: water shelter a new entertainment system clothes

Scarcity is the fundamental challenge that all individuals and nations must confront. Everyone faces some limitations, so we all have to make choices where we limit or allow ourselves to something.  Economists generally recognize four types of economic systems traditional, traditional, command, market and mixed.A traditional economic system is shaped by tradition. The work …

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Which of the following occurs during photosynthesis? A. CO2 is used to produce water B. CO2 is absorbed by mitochondria C. CO2 and H2O are converted to carbohydrates D. CO2 and H20 are combined into carbonic acid

Answer: The correct answer is a. Amy: wildlife in or near water = turtles, crayfish, goldfish non-water wildlife = fox, deer, bobcat. Explanation: According to the question students were asked to contrast their observations based on the location so according to the location, animals should be differentiated into water animals …

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A cooling tower a. is controlled by a thermostat. b. cools water as it flows through pipes. c. cools water through insulation. d. causes thermal pollution.

A cooling tower a. is controlled by a thermostat. b. cools water as it flows through pipes. c. cools water through insulation. d. causes thermal pollution.

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Dense water near the poles sinks, creating a current towards the equator. What would you expect to happen to this current if temperatures at the poles increased? A. The current would move to the surface B. Nothing would happen to the current C. The current would decrease in speed D. The current would increase in speed

The gravitational force Fg between two objects is given by the equation: Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies.  Due to the gravitational attraction the pencil and the eraser will …

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25. From left to right across a period in the periodic table, elements become less ___________ and more ______________ in their properties. 26. Francium has 36 isotopes, but only francium-223 occurs in nature. Francium-223 spontaneously emits particles and energy, so francium-223 is a(an) _____________ of francium. 27. At sea level, water ______________ at 100°C. 28. Cooking requires continuous addition of energy to the chemical reactions that are taking place. The chemical reactions involved in cooking can be described as __________________. 29. The ________________ theory of matter states that all particles of matter are in constant motion. 30. In Rutherford’s experiments, some of the _______________ aimed at gold atoms bounced back, suggesting that a solid mass was at the center of the atom. 31. You are given the melting points of three unknown substances and are asked to predict which one is an ionic compound. You would select the compound with the ________________ melting point. 32. A flight simulator that helps astronauts prepare for a shuttle launch is an example of a(an) __________________. 33. In the symbol ■([email protected]) He, the superscript 4 is the _________________ for helium, and the subscript 2 is the ___________________ for helium.

25) Answer is: less metallic and more nonmetallic. Electronegativity increases from left to right across a period, atoms have tendency to attract electrons. Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons. 26) Answer is: radioisotope. Radioisotope has an unstable …

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If your are breathless and unable to talk normally during exercise,you should immediately A. Stop and notify your doctor B. Drink more water C. Go inside to rest D. Lower your exercise level

1. The answer is “C”. “Identical twins” who have been raised apart are typically more similar in intelligence level than biological siblings raised together because they have been born with the same genetic code. Identical twins originate from a single fertilized egg that parts into two. Before it parts, it …

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Which excerpt from “The Man to Send Rain Clouds” best illustrates how Leon’s beliefs differ from those of Father Paul? “Well, I’m glad you understand. I hope I’ll be seeing you at Mass this week—we missed you last Sunday. See if you can get old Teofilo to come with you.” The priest smiled and waved at them as they drove away. Leon walked toward the old man’s bed. The red plaid shawl had been shaken and spread carefully over the bed, and a new brown flannel shirt and pair of stiff new Levi’s were arranged neatly beside the pillow. It was noontime now because the church bells rang the Angelus. They ate the beans with hot bread, and nobody said anything until after Teresa poured the coffee. Leon turned to look up at the high blue mountains in the deep snow that reflected a faint red light from the west. He felt good because it was finished, and he was happy about the sprinkling of the holy water; now the old man could send them big thunderclouds for sure.

Answer: D) Bountiful harvests, to suggest Gant’s agricultural success. Explanation: In the given excerpt we can see many sensorial details like “His grape vines thickened into brawny ropes of brown” and “And the flowers grew in rioting glory in his yard—the velvet-leaved nasturtium, slashed with a hundred tawny dyes”, these …

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The cell membrane of a red blood cell will allow water, oxygen, carbon dioxide, and glucose to pass through. Since other substances are blocked from coming in, this is membrane is called: A) perforated B) semi-permeable C) non-conductive D) permeable

Correct answer: C). Genetically different haploid cells Meiosis is a type of cell division in which four haploid cells are produced, which are genetically different from the parent. It reduces the chromosome number exactly half as contained in the parent. That is why it is called as a reductional division. …

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Consider the hydrate FeSO4 • 7H2O. What is the molar mass of this hydrate? g/mol What is the molar mass of the anhydrous salt FeSO4? g/mol What is the molar mass of water in the hydrate? g/mol

This problem is to apply Roult’s Law. Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv p = Xsolv * Po sol X solv …

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Which statement correctly compares the pH of water to that of other substances? a: The pH of water increases as its temperature increases, while other substances have a stable pH. b: The pH of water is neutral; it is higher than the pH of acids and lower than pH of bases c: Water contains more hydrogen ions than most other substances, giving it a higher pH. d: Water is neutral and has a pH of 0; acids have a pH greater than 0 and bases have a pH less than 0

In tropical rain forest, the animals will have to deal with higher temperatures and greater rainfall. One example of an adaptation they might need is a thin, water-proof coat. This will prevent heat from becoming trapped inside their fur/hair/feathers, and the water-absorbing coating will allow water to stick to the …

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Bio 1 01.04 properties of water

                                          1.04 Properties of Water Question: What effect will adding soap to water have on surface tension?   Hypothesis: If, soap is added to the water slowly dropped on a penny then, the penny will hold more water.   Independent/Dependent/Control Variables: Independent: the amount of soap/oil; Dependent: the penny; Control: …

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A metal sample is heated and placed into the water in a calorimeter at room temperature. Which statement best describes how the calorimeter can be used to determine the specific heat capacity of the metal sample? Energy transfers to the metal from the water and calorimeter until they are all at room temperature. Energy transfers from the metal to the water and calorimeter until they are all at room temperature. Energy transfers to the metal from the water and calorimeter until they all reach a single temperature. Energy transfers from the metal to the water and calorimeter until they all reach a single temperature.

This problem is to apply Roult’s Law. Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv p = Xsolv * Po sol X solv …

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Match the careers with the job tasks. Tiles 1.agricultural technician 2.hydroelectric technician 3.home appliance repairman 4.textile tender Pairs A.analyzes water for environmental issues, such as drought, pollution, or erosion B.gathers crop or animal samples for scientific testing C.operates and tends cutting machines for various textiles D. troubleshoots and repairs faulty machinery and equipment

Technician is a worker trained with special skills, especially in science and engineering. 1. Agricultural technician – gathers crop or animal samples for scientific testing. (Agricultural: used for farming or relating to farming.) 2. Hydorelectric technician – Analyzes water for envinromental issues, such as drought, pollution, or erosion. (Hydroelectric – …

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During winters freezing temperatures, some plants can remove water from their cells to reduce the amount of water that will freeze inside them. Why would plants need to do this? A. The frozen water constricts organelles and causes plant cells to shrink. B. As the water contracts during freezing, the cells would pull away from each other, causing damage. C. Less water in the cells means the cells are smaller and need to do less work. D. The expansion of excess water as it turns to ice inside the cells would break the cells apart.

Correct answer: C). Genetically different haploid cells Meiosis is a type of cell division in which four haploid cells are produced, which are genetically different from the parent. It reduces the chromosome number exactly half as contained in the parent. That is why it is called as a reductional division. …

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When 13.6 grams of kcl are dissolved in enough water to create a 180-gram solution, what is the solution’s concentration, expressed as a percent by mass? 4.6% kcl 6.8% kcl 7.6% kcl 8.2% kcl?

This problem is to apply Roult’s Law. Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv p = Xsolv * Po sol X solv …

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Write the net ionic equation for the equilibrium that is established when ammonium perchlorate is dissolved in water.

Explanation : In the net ionic equations, we are not include the spectator ions in the equations. Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides. (a) The given balanced ionic equation is, …

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