Scientific Reasoning MCQs

Question 1

A student studied the relationship between the current,voltage,and resistance in a direct circuit.To obtain the results presented in Figure 1 and Table 1,the student constructed the circuit shown below.The student used 3 resistors and different amounts of voltage generate Table 1.The current was read from the ammeter.To obtain the results in Table 1,a 5-ohm resistor (Resistor 4)was used varid .The current was measured at the power was then calculated.If the voltage in the circuit used to generate Table 1 were set at 12.5 V, the power would most nearly equal:

Accepted Answer

31.2 W

Answer

12.5 W

Answer

37.5 W

Answer

57.5 W

Question 2

Astronomers believe that stars develop from the condensation of interstellar gas clouds (IGCs) that are initially hundreds to even thousands of times more massive than the Sun. Two astronomers discuss the star formation process in these clouds.Astronomer X:Star formation begins when large fragments of a gas cloud collapse. Each of these fragments typically contains hundreds of times more gas than exists in an individual star. This collapse occurs when the gravitational attraction between the gas particles overcomes the sum of all outward forces. When collapsing gas particles in each fragment get close together, heat builds up. As a protostar begins with the inward movement of particles from the exterior of the protostar. Its collapse stops when outward forces, especially forces that result from the heating of the gas being compressed, balance the gravitational force. This brings a small region of the original cloud into equilibrium and a new star into a stable form.Astronomer Y:Stars develop when small fragments of gas clouds collapse. Calculations show that when fragmentation occurs, the fragments that form are much smaller in size than mature stars. Thus, stars develop from relatively small masses and volumes of the large IGCs called cores. A cold core collapses because of its own gravity. However, 95% of all localized cores are called protostars. The collapse of a cold core is stopped by outward forces that develop when the gas heats up. The protostar then gravitationally attracts for outer layers of the cold core together until the gas has completely transformed into a star. At early stages in development, the outer layers of the cold core are so thick that they prevent the core's light from escaping into space. Only after the outer layers have been incorporated into the star does the star become visible.In order to best test Astronomer Y's theory, how should a computer simulation look with respect to the density and temperature of a gas?

Accepted Answer

Similar to a theoretical cold core, to observe its gravitational collapse

Answer

Similar to an IGC's cold core, to observe its collapse

Answer

Higher than a typical IGC's temperature, to observe its expansion

Answer

Similar to a young star's core, to observe its fusion process

Question 3

Astronomers believe that stars develop from the condensation of interstellar gas clouds (IGCs) that are initially hundreds to even thousands of times more massive than the Sun. Two astronomers discuss the star formation process in these clouds.Astronomer X:Star formation begins when large fragments of a gas cloud collapse. Each of these fragments typically contains hundreds of times more gas than exists in an individual star. This collapse occurs when the gravitational attraction between the gas particles overcomes the sum of all outward forces. When collapsing gas particles in each fragment get close together, heat builds up. As a protostar begins with the inward movement of particles from the exterior of the protostar. Its collapse stops when outward forces, especially forces that result from the heating of the gas being compressed, balance the gravitational force. This brings a small region of the original cloud into equilibrium and a new star into a stable form.Astronomer Y:Stars develop when small fragments of gas clouds collapse. Calculations show that when fragmentation occurs, the fragments that form are much smaller in size than mature stars. Thus, stars develop from relatively small masses and volumes of the large IGCs called cores. A cold core collapses because of its own gravity. However, 95% of all localized cores are called protostars. The collapse of a cold core is stopped by outward forces that develop when the gas heats up. The protostar then gravitationally attracts for outer layers of the cold core together until the gas has completely transformed into a star. At early stages in development, the outer layers of the cold core are so thick that they prevent the core's light from escaping into space. Only after the outer layers have been incorporated into the star does the star become visible.Which of the following physical actions or properties most directly causes heating of a protostar?

Accepted Answer

Gas atoms that strike each other as the protostar collapses

Answer

Pressure from the surrounding gas

Answer

distant stars

Answer

Gravitational forces from other IGCs

Question 4

Astronomers believe that stars develop from the condensation of interstellar gas clouds (IGCs) that are initially hundreds to even thousands of times more massive than the Sun. Two astronomers discuss the star formation process in these clouds.Astronomer X:Star formation begins when large fragments of a gas cloud collapse. Each of these fragments typically contains hundreds of times more gas than exists in an individual star. This collapse occurs when the gravitational attraction between the gas particles overcomes the sum of all outward forces. When collapsing gas particles in each fragment get close together, heat builds up. As a protostar begins with the inward movement of particles from the exterior of the protostar. Its collapse stops when outward forces, especially forces that result from the heating of the gas being compressed, balance the gravitational force. This brings a small region of the original cloud into equilibrium and a new star into a stable form.Astronomer Y:Stars develop when small fragments of gas clouds collapse. Calculations show that when fragmentation occurs, the fragments that form are much smaller in size than mature stars. Thus, stars develop from relatively small masses and volumes of the large IGCs called cores. A cold core collapses because of its own gravity. However, 95% of all localized cores are called protostars. The collapse of a cold core is stopped by outward forces that develop when the gas heats up. The protostar then gravitationally attracts for outer layers of the cold core together until the gas has completely transformed into a star. At early stages in development, the outer layers of the cold core are so thick that they prevent the core's light from escaping into space. Only after the outer layers have been incorporated into the star does the star become visible.Which of the following hypotheses would Astronomer Y most likely make if a new star suddenly appeared in IGC?

Accepted Answer

A collapsing fragment of gas has become dense enough to begin shining

Answer

A cold core has incorporated its outer layers

Answer

Reflected light from our sun is seen bouncing off the IGC

Answer

The force of gravity has joined several fragments of a collapsing cloud

Question 5

Astronomers believe that stars develop from the condensation of interstellar gas clouds (IGCs) that are initially hundreds to even thousands of times more massive than the Sun. Two astronomers discuss the star formation process in these clouds.Astronomer X:Star formation begins when large fragments of a gas cloud collapse. Each of these fragments typically contains hundreds of times more gas than exists in an individual star. This collapse occurs when the gravitational attraction between the gas particles overcomes the sum of all outward forces. When collapsing gas particles in each fragment get close together, heat builds up. As a protostar begins with the inward movement of particles from the exterior of the protostar. Its collapse stops when outward forces, especially forces that result from the heating of the gas being compressed, balance the gravitational force. This brings a small region of the original cloud into equilibrium and a new star into a stable form.Astronomer Y:Stars develop when small fragments of gas clouds collapse. Calculations show that when fragmentation occurs, the fragments that form are much smaller in size than mature stars. Thus, stars develop from relatively small masses and volumes of the large IGCs called cores. A cold core collapses because of its own gravity. However, 95% of all localized cores are called protostars. The collapse of a cold core is stopped by outward forces that develop when the gas heats up. The protostar then gravitationally attracts for outer layers of the cold core together until the gas has completely transformed into a star. At early stages in development, the outer layers of the cold core are so thick that they prevent the core's light from escaping into space. Only after the outer layers have been incorporated into the star does the star become visible.If Astronomer X is correct ,which of the following is most likely to initially occur when 2 ICGs in which no stars are forming collide?

Accepted Answer

Cold cores forming near the boundary of the collision

Answer

Cold cores forming far from the boundary of the collision

Answer

Individual stars collapsing near the boundary of the collision

Answer

Large volumes of gas collapsing together near the boundary of the collision

Question 6

Astronomers believe that stars develop from the condensation of interstellar gas clouds (IGCs) that are initially hundreds to even thousands of times more massive than the Sun. Two astronomers discuss the star formation process in these clouds.Astronomer X:Star formation begins when large fragments of a gas cloud collapse. Each of these fragments typically contains hundreds of times more gas than exists in an individual star. This collapse occurs when the gravitational attraction between the gas particles overcomes the sum of all outward forces. When collapsing gas particles in each fragment get close together, heat builds up. As a protostar begins with the inward movement of particles from the exterior of the protostar. Its collapse stops when outward forces, especially forces that result from the heating of the gas being compressed, balance the gravitational force. This brings a small region of the original cloud into equilibrium and a new star into a stable form.Astronomer Y:Stars develop when small fragments of gas clouds collapse. Calculations show that when fragmentation occurs, the fragments that form are much smaller in size than mature stars. Thus, stars develop from relatively small masses and volumes of the large IGCs called cores. A cold core collapses because of its own gravity. However, 95% of all localized cores are called protostars. The collapse of a cold core is stopped by outward forces that develop when the gas heats up. The protostar then gravitationally attracts for outer layers of the cold core together until the gas has completely transformed into a star. At early stages in development, the outer layers of the cold core are so thick that they prevent the core's light from escaping into space. Only after the outer layers have been incorporated into the star does the star become visible.Is the observation by Astronomer X that almost all young stars are found in clusters consistent with the theory of Astronomer Y?

Accepted Answer

No: cold cores pull in all material close to them

Answer

Yes: the sub-fragments of fragments of the cloud that form stars attract each other gravitationally

Answer

Yes: the gas cloud where individual stars form is a relatively compact object

Answer

No: the stars. Once formed drift away from each other

Question 7

PASSAGE:Astronomers believe that stars develop from the condensation of interstellar gas clouds (IGCs) that are initially hundreds to even thousands of times more massive than the Sun. Two astronomers discuss the star formation process in these clouds.Astronomer X:Star formation begins when large fragments of a gas cloud collapse. Each of these fragments typically contains hundreds of times more gas than exists in an individual star. This collapse occurs when the gravitational attraction between the gas particles overcomes the sum of all outward forces. When collapsing gas particles in each fragment get close together, heat builds up. As a protostar begins with the inward movement of particles from the exterior of the protostar. Its collapse stops when outward forces, especially forces that result from the heating of the gas being compressed, balance the gravitational force. This brings a small region of the original cloud into equilibrium and a new star into a stable form.Astronomer Y:Stars develop when small fragments of gas clouds collapse. Calculations show that when fragmentation occurs, the fragments that form are much smaller in size than mature stars. Thus, stars develop from relatively small masses and volumes of the large IGCs called cores. A cold core collapses because of its own gravity. However, 95% of all localized cores are called protostars. The collapse of a cold core is stopped by outward forces that develop when the gas heats up. The protostar then gravitationally attracts for outer layers of the cold core together until the gas has completely transformed into a star. At early stages in development, the outer layers of the cold core are so thick that they prevent the core's light from escaping into space. Only after the outer layers have been incorporated into the star does the star become visible.If Astronomer X is correct, the density of a newly forming star, over time, should be predicted to:

Accepted Answer

Decrease forever

Answer

Decrease until it reaches a fairly constant value

Answer

Increase until it reaches a fairly constant value

Answer

Remain constant

Question 8

Study of velocity and kinetic energy, a cart was tested in 9 different trials. The cart carried different masses down 3 different inclinations. Table I shows the mass carried by the cart, the height from which it was released.And that is rolled to get to the end of the ramp. The table also lists the speed and kinetic energy of the cart released the of the ramp.Which of the following pairs of trials supports the conclusion that the distance rolled on each ramp is directly proportional to the height of release?

Accepted Answer

Trials 2 and 8

Answer

Trials 2 and 3

Answer

Trials 2 and 5

Answer

Trials 5 and 8

Question 9

Study of velocity and kinetic energy, a cart was tested in 9 different trials. The cart carried different masses down 3 different inclinations. Table I shows the mass carried by the cart, the height from which it was released.And that is rolled to get to the end of the ramp. The table also lists the speed and kinetic energy of the cart released the of the ramp.Which of the following variables was a content in Trials 2 and 5?

Accepted Answer

Mass

Answer

Height

Answer

Speed

Answer

Kinetic energy

Question 10

Study of velocity and kinetic energy, a cart was tested in 9 different trials. The cart carried different masses down 3 different inclinations. Table I shows the mass carried by the cart, the height from which it was released.And that is rolled to get to the end of the ramp. The table also lists the speed and kinetic energy of the cart released the of the ramp.Doubling both the mass of the cart and the height from which it is released changes the kinetic energy by a factors of

Accepted Answer

4

Answer

1/2

Answer

2

Answer

1/4

Question 11

Study of velocity and kinetic energy, a cart was tested in 9 different trials. The cart carried different masses down 3 different inclinations. Table I shows the mass carried by the cart, the height from which it was released.And that is rolled to get to the end of the ramp. The table also lists the speed and kinetic energy of the cart released the of the ramp.Which of the following relationships between mass and kinetic energy is indicated by the data for Trials 3 and 5

Accepted Answer

Mass is directly proportional to kinetic energy

Answer

Mass is inversely proportional to kinetic energy

Answer

Mass squared is proportional to kinetic energy

Answer

Mass is directly proportional to kinetic energy squared

Question 12

Study of velocity and kinetic energy, a cart was tested in 9 different trials. The cart carried different masses down 3 different inclinations. Table I shows the mass carried by the cart, the height from which it was released.And that is rolled to get to the end of the ramp. The table also lists the speed and kinetic energy of the cart released the of the ramp.What kinetic energy would be calculated if the cart had carried 8 kg and had been released from a height of 16m in Ramp 1?

Accepted Answer

640 joules

Answer

400 joules

Answer

960 joules

Answer

1,280 joules

Question 13

Study of velocity and kinetic energy, a cart was tested in 9 different trials. The cart carried different masses down 3 different inclinations. Table I shows the mass carried by the cart, the height from which it was released.And that is rolled to get to the end of the ramp.The data indicate that compared to Ramp 2.Ramp 1 is:

Accepted Answer

Higher

Answer

Smoother

Answer

Steeper

Answer

Less steep

Question 14

The rate of a chemical reaction is obtained by dividing the amount of a chemical consumed in a reaction by the time in which the chemical is consumed. The rate at which a chemical reaction occurs is dependent on many variables, two of which are the concentration of a chemical in solution and the temperature at which the reaction occurs. In order to determine the effect of concentration and temperature on reaction rates, a chemist studied the following reaction sequence.HCHO + Na2SO3 + H2O → NaO3SOCH3 + NaOHReaction 1NaOH+ NaHSO3 → Na2SO3 + H2OReaction 2While Reaction 1 occurs slowly, Reaction 2 happens instantaneously. Both of the reactions occur in the same solution and base (NaOH) is built up in solution until all the NaHSO3 is used. Phenolphthalein, which is also in the solution, will cause the solution to turn pink when a measurable amount of base is present.Experiment 1:A standard solution of formaldehyde (HCHO) in water was prepared. This solution contained 0.3 mole of HCHO per liter of solution (0.3 M HCHO) and a small amount of phenolphthalein. This solution was diluted further with varying amounts of water and mixed with 10.0 mL of a 0.01 M solution of both Na2SO3 and NaHSO3 in water. The time required for pink color to appear is shown in Table 1.In order to display the relationship between concentration and the rate of the reaction more effectively in Experiment 1, the chemist could:

Accepted Answer

Make a bar graph of the concentration of formaldehyde in each trial

Answer

Plot the HCHO concentration against the time required for the color change

Answer

Plot the change in tHCHO and NaHSO3 in each trial against that in HCHO concentrations

Answer

Produce a dual cataloging: the differences between the times for the color change in successive trials

Question 15

The rate of a chemical reaction is obtained by dividing the amount of a chemical consumed in a reaction by the time in which the chemical is consumed. The rate at which a chemical reaction occurs is dependent on many variables, two of which are the concentration of a chemical in solution and the temperature at which the reaction occurs. In order to determine the effect of concentration and temperature on reaction rates, a chemist studied the following reaction sequence.HCHO + Na2SO3 + H2O → NaO3SOCH3 + NaOHReaction 1NaOH+ NaHSO3 → Na2SO3 + H2OReaction 2While Reaction 1 occurs slowly, Reaction 2 happens instantaneously. Both of the reactions occur in the same solution and base (NaOH) is built up in solution until all the NaHSO3 is used. Phenolphthalein, which is also in the solution, will cause the solution to turn pink when a measurable amount of base is present.Experiment 1:A standard solution of formaldehyde (HCHO) in water was prepared. This solution contained 0.3 mole of HCHO per liter of solution (0.3 M HCHO) and a small amount of phenolphthalein. This solution was diluted further with varying amounts of water and mixed with 10.0 mL of a 0.01 M solution of both Na2SO3 and NaHSO3 in water. The time required for pink color to appear is shown in Table 1.Which of the following trials in Experiment 1 had the same concentration of HCHO as in all the trials of Experiment 2?

Accepted Answer

Trial 4

Answer

Trial 2

Answer

Trial 8

Answer

Trial 9

Question 16

The rate of a chemical reaction is obtained by dividing the amount of a chemical consumed in a reaction by the time in which the chemical is consumed. The rate at which a chemical reaction occurs is dependent on many variables, two of which are the concentration of a chemical in solution and the temperature at which the reaction occurs. In order to determine the effect of concentration and temperature on reaction rates, a chemist studied the following reaction sequence.HCHO + Na2SO3 + H2O → NaO3SOCH3 + NaOHReaction 1NaOH+ NaHSO3 → Na2SO3 + H2OReaction 2While Reaction 1 occurs slowly, Reaction 2 happens instantaneously. Both of the reactions occur in the same solution and base (NaOH) is built up in solution until all the NaHSO3 is used. Phenolphthalein, which is also in the solution, will cause the solution to turn pink when a measurable amount of base is present.Experiment 1:A standard solution of formaldehyde (HCHO) in water was prepared. This solution contained 0.3 mole of HCHO per liter of solution (0.3 M HCHO) and a small amount of phenolphthalein. This solution was diluted further with varying amounts of water and mixed with 10.0 mL of a 0.01 M solution of both Na2SO3 and NaHSO3 in water. The time required for pink color to appear is shown in Table 1.If Reaction 1 was found to be exothermic (heat producing), How could Experiment 1 be modified to examine only the effect of concentration on reaction rate?

Accepted Answer

The concentration of HCHO could be increased

Answer

The temperature of the solution could be increased

Answer

The concentration of formaldehyde could be used to determine the color change

Answer

A different method could be used to set the solution to a constant temperature

Question 17

The rate of a chemical reaction is obtained by dividing the amount of a chemical consumed in a reaction by the time in which the chemical is consumed. The rate at which a chemical reaction occurs is dependent on many variables, two of which are the concentration of a chemical in solution and the temperature at which the reaction occurs. In order to determine the effect of concentration and temperature on reaction rates, a chemist studied the following reaction sequence.HCHO + Na2SO3 + H2O → NaO3SOCH3 + NaOHReaction 1NaOH+ NaHSO3 → Na2SO3 + H2OReaction 2While Reaction 1 occurs slowly, Reaction 2 happens instantaneously. Both of the reactions occur in the same solution and base (NaOH) is built up in solution until all the NaHSO3 is used. Phenolphthalein, which is also in the solution, will cause the solution to turn pink when a measurable amount of base is present.Experiment 1:A standard solution of formaldehyde (HCHO) in water was prepared. This solution contained 0.3 mole of HCHO per liter of solution (0.3 M HCHO) and a small amount of phenolphthalein. This solution was diluted further with varying amounts of water and mixed with 10.0 mL of a 0.01 M solution of both Na2SO3 and NaHSO3 in water. The time required for pink color to appear is shown in Table 1.The fastest rate of reaction in Experiment 1 occurred when:

Accepted Answer

The concentration of NaOH was greatest in the reaction mixture

Answer

The time for the color change to occur was greatest

Answer

The concentration of NaOH was smallest in the reaction mixture

Answer

The concentration of HCHO was greatest in the reaction mixture

Question 18

The rate of a chemical reaction is obtained by dividing the amount of a chemical consumed in a reaction by the time in which the chemical is consumed. The rate at which a chemical reaction occurs is dependent on many variables, two of which are the concentration of a chemical in solution and the temperature at which the reaction occurs. In order to determine the effect of concentration and temperature on reaction rates, a chemist studied the following reaction sequence.HCHO + Na2SO3 + H2O → NaO3SOCH3 + NaOHReaction 1NaOH+ NaHSO3 → Na2SO3 + H2OReaction 2While Reaction 1 occurs slowly, Reaction 2 happens instantaneously. Both of the reactions occur in the same solution and base (NaOH) is built up in solution until all the NaHSO3 is used. Phenolphthalein, which is also in the solution, will cause the solution to turn pink when a measurable amount of base is present.Experiment 1:A standard solution of formaldehyde (HCHO) in water was prepared. This solution contained 0.3 mole of HCHO per liter of solution (0.3 M HCHO) and a small amount of phenolphthalein. This solution was diluted further with varying amounts of water and mixed with 10.0 mL of a 0.01 M solution of both Na2SO3 and NaHSO3 in water. The time required for pink color to appear is shown in Table 1.Which of the following experiments would most likely produce more information about other variables that affect the rates of these reactions?

Accepted Answer

Conducting Experiment 1 with smaller amounts of HCHO

Answer

Conducting Experiment 1 with larger concentrations of HCHO

Answer

Adding NaOH to the HCHO solution in Experiment 1

Answer

Varying the concentrations of Na2SO3 and NaHSO3 while keeping the HCHO concentration constant

Question 19

The rate of a chemical reaction is obtained by dividing the amount of a chemical consumed in a reaction by the time in which the chemical is consumed. The rate at which a chemical reaction occurs is dependent on many variables, two of which are the concentration of a chemical in solution and the temperature at which the reaction occurs. In order to determine the effect of concentration and temperature on reaction rates, a chemist studied the following reaction sequence.HCHO + Na2SO3 + H2O → NaO3SOCH3 + NaOHReaction 1NaOH+ NaHSO3 → Na2SO3 + H2OReaction 2While Reaction 1 occurs slowly, Reaction 2 happens instantaneously. Both of the reactions occur in the same solution and base (NaOH) is built up in solution until all the NaHSO3 is used. Phenolphthalein, which is also in the solution, will cause the solution to turn pink when a measurable amount of base is present.Experiment 1:A standard solution of formaldehyde (HCHO) in water was prepared. This solution contained 0.3 mole of HCHO per liter of solution (0.3 M HCHO) and a small amount of phenolphthalein. This solution was diluted further with varying amounts of water and mixed with 10.0 mL of a 0.01 M solution of both Na2SO3 and NaHSO3 in water. The time required for pink color to appear is shown in Table 1.The function of phenolphthalein in both experiments was to:

Accepted Answer

Signal when the NaOH was completely used up

Answer

Signal when the HCHO was completely consumed

Answer

React with the HCHO solution

Answer

Alter the rate of reaction

Question 20

A newsagent sells four different puzzle magazines. Information about these magazines is given in the following table.Jemina went into the newsagent yesterday to buy one of these magazines. She chose the one that offered her the least cost per puzzle.Which magazine did Jemina choose?

Accepted Answer

Puzzlemania

Answer

Number Crunch

Answer

Thinking Today

Answer

Mathematical Genius

Free Scientific Reasoning MCQs with Answers