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Which statement best describes the use of catalytic converters in automobiles? A. They decrease the rate of the reactions that produce harmful gases. B. They oxidize hydrocarbons to form less toxic gases. C. They combine the larger hydrocarbon molecules with smaller ones. D. They increase reaction temperature for cleaner burning.

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Answer:  B. They oxidize hydrocarbons to form less toxic gases.

Explanation:

A catalytic converter is a device which is used in automobile engine to convert the harmful gaseous exhaust into a less toxic pollutant after the process of combustion of the fuel. It conducts an internal redox (oxidation-reduction) reaction in the automobile engine to facilitate such conversion.

On the basis of the above information, They oxidize hydrocarbons to form less toxic gases is the correct option.

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Which statement about weight control is false exercise help to control our way by burning calories to lose weight we need to burn more calories than we consume each day people burn calories at different rates depending on metabolism weight control is the primary benefit of exercise

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Which statement about weight control is false exercise help to control our way by burning calories to lose weight we need to burn more calories than we consume each day people burn calories at different rates depending on metabolism weight control is the primary benefit of exercise

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Which of the following was an effective weapon in WWI because the vapors given off caused burning, swelling of nose, throat, and eyes, and often death?

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The most effective weapons were poisonous gasses. The example that you gave will be the mustard gas, which was commonly used by both sides during the war. These weapons were so effective to the point they were banned from being used after the war.

hope this helps 😀

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– How many moles of NaHCO3 can be produced from 125 mol of NaCl – How many moles Of H2O are produced when 6 mol of O2 is consumed in burning methyl alcohol, CH3OH, according to the following equation? – Solutions of iron(III) chloride, FeCl3, are used in photoengraving and to make ink. This compound can be made by the following reaction. a. How many moles of FeCl3 form from 31 mol of Cl2? b. How many moles of Fe are needed to combine with 5 mol of Cl2 by this reaction? c. If 0.62 mol of Fe is to be used by this reaction, how many moles of FeCl3 form? – Ammonia is produced synthetically by the reaction: a. Is this an exothermic or endothermic process? b. How many moles of NH3 are formed when 1 mol of N2 reacts with hydrogen? c. If 18 x 1023 molecules of H2 react with nitrogen, how many moles of NH3 are produced?

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A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.

Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).

For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.

Activation energy of reverse and forward reactions is related by:

Activation energy of reverse rxn = Activation energy of forward rxn – ΔH rxn

=> Activiation energy of reverse rxn = 102 kJ/mol – 55 kJ/mol = 47 kJ/mol

Answer: 47 kJ/mol

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Why is indoor air pollution a serious health hazard in some developing countries? a. the burning of coal releases significant amounts of particulates into the air. b. people smoke more in developing countries. c. many homes rely on indoor burning of wood or dung without proper ventilation. d. most houses in these countries are well insulated, increasing household exposure to radiation?

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Why is indoor air pollution a serious health hazard in some developing countries? a. the burning of coal releases significant amounts of particulates into the air. b. people smoke more in developing countries. c. many homes rely on indoor burning of wood or dung without proper ventilation. d. most houses in these countries are well insulated, increasing household exposure to radiation?

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Read this stanza from "The Raven." Back into the chamber turning, all my soul within me burning, Soon again I heard a tapping something louder than before. "Surely," said I, "surely that is something at my window lattice; Let me see, then, what thereat is and this mystery explore– Let my heart be still a moment and this mystery explore;– 'Tis the wind and nothing more." This stanza contributes to the suspense of the poem because a) the reader knows what is making the noise while the speaker does not. b) the speaker and the reader wait again to find out what is making the noise. c) the tapping gets louder, which foreshadows that the noise is made by a bird. d) the wind gets stronger and makes more noise against the speaker’s window.

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Read this stanza from “The Raven.” Back into the chamber turning, all my soul within me burning, Soon again I heard a tapping something louder than before. “Surely,” said I, “surely that is something at my window lattice; Let me see, then, what thereat is and this mystery explore– Let my heart be still a moment and this mystery explore;– ‘Tis the wind and nothing more.” This stanza contributes to the suspense of the poem because a) the reader knows what is making the noise while the speaker does not. b) the speaker and the reader wait again to find out what is making the noise. c) the tapping gets louder, which foreshadows that the noise is made by a bird. d) the wind gets stronger and makes more noise against the speaker’s window.

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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

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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 new value for the resistance is R=1.18*R₀.

T₀=20°C
=0.0068
R=1.18*R₀

Now we need to input that into the equation for resistance change and solve for temperature T.  

1.18R₀=R₀(1+α(T-20)), R₀ cancels out,

1.18=1+α(T-20),

1.18-1=α(T-20), we divide by α,

0.18/α=T-20, we put 20 on the left side,

26.47+20=T

T=46.47°C

So the temperature on which the resistance of copper wire will increase by 18% is T=46.47°C. 

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Which excerpt from “The Scarlet Ibis” most foreshadows that the narrator will feel regret for something he has done to Doodle? But sometimes (like right now), as I sit in the cool, green-draped parlor, the grindstone begins to turn, and time with all its changes is ground away—and I remember Doodle. Doodle was my brother and he was going to cling to me forever, no matter what I did, so I dragged him across the burning cotton field to share with him the only beauty I knew, Old Woman Swamp. There is within me (and with sadness I have watched it in others) a knot of cruelty borne by the stream of love, much as our blood sometimes bears the seed of our destruction, and at times I was mean to Doodle. Once I had succeeded in teaching Doodle to walk, I began to believe in my own infallibility and I prepared a terrific development program for him, unknown to Mama and Daddy, of course.

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Answer:

Gather references, and prepare your résumé.

Explanation:

Before a job interview, it is advisable to prepare a copy of your résumé and references, as well as bring a pen and notepad.

The rest of the alternatives are incorrect because asking the company to keep your rĂ©sumĂ© on file is inappropriate – you should always carry a copy of  it; asking and answering questions politely happens during the course of the interview; and restating your interest is done after the interview has occurred.

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A 5.45-g combustible sample is burned in a calorimeter. the heat generated changes the temperature of 555 g of water from 20.5°c to 39.5°c. how much energy is released by the burning? the specific heat of water is 4.18 j/ (°c × g). 564 j 2,500 j 44,100 j 138,000 j

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A 5.45-g combustible sample is burned in a calorimeter. the heat generated changes the temperature of 555 g of water from 20.5°c to 39.5°c. how much energy is released by the burning? the specific heat of water is 4.18 j/ (°c × g). 564 j 2,500 j 44,100 j 138,000 j

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Match the term to its description. 1. deforestation 2. combustion 3. circulation 4. weathering 5. calcium carbonate a. the primary component of mollusk shells and coral skeletons b. the logging of trees, which removes producers from the carbon cycle c. the burning of fossil fuels to make energy d. the process which brings up nutrients from the deep ocean e. the wearing down of rocks over time

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Answer:

The integumentary system covers the surface of the body is true about the integumentry system.

Explanation:

The integumentary system includes the skin, nails, glands, hairs, and nerves. Its main role is to act as a barrier to protect the body from the outside environment. It also retains body fluids, regulates body temperature, eliminates waste products, and protects against disease.

The integumentary system is the largest organ in the body that covers the surface of the body.

Thus, The integumentary system covers the surface of the body is the true statement about the integumentry system.

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In a nuclear power plant, mechanical energy is created by turning a turbine from steam created by heating water from which of the following? A)the burning of uranium B)the fusion of uranium C)the fission of uranium

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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 new value for the resistance is R=1.18*R₀.

T₀=20°C
=0.0068
R=1.18*R₀

Now we need to input that into the equation for resistance change and solve for temperature T.  

1.18R₀=R₀(1+α(T-20)), R₀ cancels out,

1.18=1+α(T-20),

1.18-1=α(T-20), we divide by α,

0.18/α=T-20, we put 20 on the left side,

26.47+20=T

T=46.47°C

So the temperature on which the resistance of copper wire will increase by 18% is T=46.47°C. 

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After Hitler became dictator, he a.ordered the burning of the Reichstag. b.arrested and jailed Weimar officials. c.banned all opposing political parties. d.blamed socialists for Germany’s problems.

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After Hitler became dictator, he a.ordered the burning of the Reichstag. b.arrested and jailed Weimar officials. c.banned all opposing political parties. d.blamed socialists for Germany’s problems.

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When a person is experiencing heartburn, he or she feels a burning sensation in the throat and midchest. Think about the structures of the digestive system. What most likely causes the burning sensation? The muscle at the end of the esophagus is not able to close, which allows stomach acid and digested food to go back up into the esophagus. The villi in the small intestine are producing extra acid that is then concentrated at the pharynx. The esophagus goes into muscle spasms while the salivary glands produce excess acid. Too much water absorption in the large intestine disrupts the pH of the digestive system, causing acid to reenter the stomach.

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The correct answer is D.  They are both vascular plants, but conifers are gymnosperms, and anthophytes are angiosperms

Anthophytes are the angiosperms or flowering plants which is the largest phylum of plants whereas, conifers such as Pines, Fir are the members of gymnosperms. Both are vascular plants, reproduce sexually to produce seeds but in conifers seed are not enclosed in fruits, thus seeds are naked in them. Anthophytes seeds are enclosed in fruits.  

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In which calculation would the use of the mass-energy equivalence principle be needed? A. energy obtained from the burning of fossil fuels B. energy given off by a current flowing through a wire C. energy created by the conversion of mass of a uranium sample D. mass of coal burned in order to provide the energy needed for a large city

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In evolutionary biology, mimicry is a similarity of one organism, usually an animal, to another that has evolved because the resemblance is selectively favoured by the behaviour of a shared signal receiver that can respond to both.[1] Mimicry may evolve between different species, or between individuals of the same species. Often, mimicry evolves to protect a species from predators, making it an antipredator adaptation.[2] The resemblances that evolve in mimicry can be in appearance, behaviour, sound or scent. Mimicry may be to the advantage of both organisms that share a resemblance, in which case it is a mutualism, or mimicry can be to the detriment of one, making it parasitic or competitive. Mimicry occurs when a group of organisms,[a] the mimics, evolve to share perceived characteristics with another group, the models. The evolutionary convergence between groups is driven by the selective action of a signal-receiver or dupe.[3] Birds, for example, use sight to identify palatable insects, whilst avoiding the noxious ones. Over time, palatable insects may evolve to resemble noxious ones, making them mimics and the noxious ones models. In the case of mutualism, sometimes both groups are referred to as “co-mimics”. It is often thought that models must be more abundant than mimics, but this is not always so.[4] Mimicry may involve numerous species; many harmless species such as hoverflies are Batesian mimics of strongly defended species such as wasps, while many such well-defended species form Mullerian mimicry rings, all resembling each other. Mimicry between prey species and their predators often involves three or more species.[5]

In its broadest definition, mimicry can include non-living models. The specific terms masquerade and mimesis are sometimes used when the models are inanimate.[6][7][8] For example, animals such as flower mantises, planthoppers and geometer moth caterpillars resemble twigs, bark, leaves or flowers.[7][4][9] Many animals bear eyespots, which are hypothesized to resemble the eyes of larger animals. They may not resemble any specific organism’s eyes, and whether or not animals respond to them as eyes is also unclear.[10] Nonetheless, eyespots are the subject of a rich contemporary literature.[11][12][13] The model is usually another species, except in automimicry, where members of the species mimic other members, or other parts of their own bodies, and in inter-sexual mimicry, where members of one sex mimic members of the other.[4]

Mimesis in Ctenomorphodes chronus, camouflaged as a eucalyptus twig

Though visual mimicry through animal coloration is most obvious to humans, other senses such as olfaction (smell) or hearing may be involved, and more than one type of signal may be employed.[7][5] Mimicry may involve morphology, behaviour, and other properties. In any case, the mimetic signal always functions because it resembles that of another organism. In evolutionary terms, this phenomenon is a form of co-evolution. It can involve an evolutionary arms race if mimicry negatively affects the model, and the model can evolve a different appearance from the mimic.[4]p161 Mimicry should not be confused with other forms of convergent evolution, which occurs when species come to resemble each other by adapting to similar lifestyles that have nothing to do with a common signal receiver. Mimics may have different models for different life cycle stages, or they may be polymorphic, with different individuals imitating different models. Models themselves may have more than one mimic, though frequency dependent selection favours mimicry where models outnumber mimics. Models tend to be relatively closely related organisms,[14] but mimicry of vastly different species is also known. Most known mimics are insects,[7] though many other animal mimics are known. Plants and fungi may also be mimics, though less research has been carried out in this area.[15][16][17]

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Compare the food energy in calories from burning the chip and the saltine. How can you explain this differences in terms of chemical composition? A) The chip contains more lipids than the saltine. B) The saltine is a carbohydrate; the chip is a lipid. C) The saltine has less protein content than the chip. D) The chip is composed of starch; the saltine of simple sugars.

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17. The SI unit for force is N.

18. When an Unbalanced force acts upon and object, the object will change speed and/or direction of motion.

19. Average speed is the speed averaged over a span of time. Instantaneous speed would be the speed at any given instance during that span of time.

20. Acceleration= (final velocity – initial velocity) / time

Final velocity= 0 m/s
Initial velocity= 25 m/s
Time = 40 sec.

So, acceleration (0 – 25) m/s / 40 sec.

Acceleration = -0.625 m/s^2

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