This document contains a 10 question multiple choice science exam covering topics like physics, chemistry, and biology. The questions test understanding of concepts like energy transformations in engines, measuring meteorological variables, electrical charge, heat transfer, temperature changes over time, concentration of solutions, atomic structure, and genetics.
1 SPU 25 Energy and Climate Vision for the Future, Spri.docxhoney725342
1
SPU 25 Energy and Climate: Vision for the Future, Spring 2018
Homework Set #1 Climate Basics, DUE Monday 2/12 (1:00 pm in lecture)
Name: _____________________________________ Section: __________ TF: _____________________ Score: ______/_______
Collaborators: _________________________________________________________________________________________________
Earth’s climate is a complex reflection of the distribution and movement of energy around the planet. The
primary source of Earth’s energy is radiation from the Sun. In this problem set, you will see how this energy is
received, lost, and stored, and the role of greenhouse gases in altering the climate. You will also understand
how the distribution of energy influences climate and get some practice with basic quantitative problems and
unit conversions. (40 points total)
You will only receive credit if you show all your work and write legibly.
I. Earth’s Energy Balance
Planet Earth (including the solid earth, oceans, and atmosphere) is best described as an isolated system:
energy, but not mass, can pass from Earth to space and vice versa. In this type of system, the energy balance
may be described by: Energy gained = Energy lost – change in storage.
1. Greenhouse gases in the atmosphere prevent the radiation of energy to space, so they impact which
term in the above equation? (1 point)
2. Changing surface and ocean temperatures reflect which term in the above equation? (1 point)
II. Energy from the Sun
3. True or False: Summer is warmer than winter because the Earth is closer to the Sun. (1 point)
4. Currently, the energy from the Sun arriving at Earth’s orbital position amounts to 1,379 W m-2,
measured perpendicular to the direction of the sunlight (see figure below).
a. Given that the Earth is a circular target for this energy and has a radius of 6.38 x 103 km,
calculate the total rate at which solar energy is intercepted by the Earth. Report your answer in
Watts. Recall that the area of a circle is πr2. (2 points)
Figure 1. The shadow formed by an
illuminated sphere has a circular
shape with a radius R equal to the
radius of the sphere.
2
b. Assuming that the energy from the Sun is eventually distributed equally over the entire surface
area of the Earth, use your answer from part (a) to calculate the current average rate of
incoming solar radiation. Express your answer in Watts per meter squared. Recall that the
surface area of a sphere is 4πr2. (3 points)
III. The fate of energy from the Sun
5. Based on your answers from the previous problem and assuming a global average albedo of 0.3, how
much of the incoming solar radiation is reflected back into space? How much is absorbed? Express
your answers in Watts per meter squared. (2 points)
6. Much of the energy absorbed at the Earth’s surface is used for evaporation. The energy involved in
changing the phase of water is c ...
1 SPU 25 Energy and Climate Vision for the Future, Spri.docxhoney725342
1
SPU 25 Energy and Climate: Vision for the Future, Spring 2018
Homework Set #1 Climate Basics, DUE Monday 2/12 (1:00 pm in lecture)
Name: _____________________________________ Section: __________ TF: _____________________ Score: ______/_______
Collaborators: _________________________________________________________________________________________________
Earth’s climate is a complex reflection of the distribution and movement of energy around the planet. The
primary source of Earth’s energy is radiation from the Sun. In this problem set, you will see how this energy is
received, lost, and stored, and the role of greenhouse gases in altering the climate. You will also understand
how the distribution of energy influences climate and get some practice with basic quantitative problems and
unit conversions. (40 points total)
You will only receive credit if you show all your work and write legibly.
I. Earth’s Energy Balance
Planet Earth (including the solid earth, oceans, and atmosphere) is best described as an isolated system:
energy, but not mass, can pass from Earth to space and vice versa. In this type of system, the energy balance
may be described by: Energy gained = Energy lost – change in storage.
1. Greenhouse gases in the atmosphere prevent the radiation of energy to space, so they impact which
term in the above equation? (1 point)
2. Changing surface and ocean temperatures reflect which term in the above equation? (1 point)
II. Energy from the Sun
3. True or False: Summer is warmer than winter because the Earth is closer to the Sun. (1 point)
4. Currently, the energy from the Sun arriving at Earth’s orbital position amounts to 1,379 W m-2,
measured perpendicular to the direction of the sunlight (see figure below).
a. Given that the Earth is a circular target for this energy and has a radius of 6.38 x 103 km,
calculate the total rate at which solar energy is intercepted by the Earth. Report your answer in
Watts. Recall that the area of a circle is πr2. (2 points)
Figure 1. The shadow formed by an
illuminated sphere has a circular
shape with a radius R equal to the
radius of the sphere.
2
b. Assuming that the energy from the Sun is eventually distributed equally over the entire surface
area of the Earth, use your answer from part (a) to calculate the current average rate of
incoming solar radiation. Express your answer in Watts per meter squared. Recall that the
surface area of a sphere is 4πr2. (3 points)
III. The fate of energy from the Sun
5. Based on your answers from the previous problem and assuming a global average albedo of 0.3, how
much of the incoming solar radiation is reflected back into space? How much is absorbed? Express
your answers in Watts per meter squared. (2 points)
6. Much of the energy absorbed at the Earth’s surface is used for evaporation. The energy involved in
changing the phase of water is c ...
CHAPTER 1 QUESTIONS (32 points total)1. List six environmental .docxsleeperharwell
CHAPTER 1 QUESTIONS: (32 points total)
1. List six environmental dilemmas that we now face and summarize how each concerns us (12 points)
2. What is extreme poverty, and why should we care? (5 points)
3. Why should we be worried about economic growth in China? (5 points)
4. How much would it cost to eliminate acute poverty and ensure basic human needs for everyone? (5 points)
5. Why are indigenous people important as guardians of nature? (5 points)
CHAPTER 2 QUESTIONS: (36 points total)
1. Why are widely accepted, well-defended scientific explanations called “theories”? (5 points)
2. Draw a diagram showing the steps of the scientific method, and explain why each is important. (12 points)
3. What is positive feedback loop? What is a negative feedback loop? Give an example of each. (8 points)
4. Why do we say that proof is elusive in science? (5 points)
5. What is a manipulative experiment? A natural experiment? A controlled study? (6 points)
Matter, Energy, and Life
ENSC 1410
Chapter 3 Quiz
NAME: ______ _____________ Section: _____ Date: _________________
I. MULTIPLE CHOICE (4 points each)
1. How are matter and mass related?
A. Mass is a component of matter
B. Neither matter nor mass take up space
C. Matter is a component of mass
D. Both matter and mass take up space
E. Mass takes up space while matter does not take up space
2. The law of conservation of matter tells us that matter
A. Can never be reused
B. Needs to be conserved or it will not be available for future generations
C. Can be destroyed
D. Can be conserved by some adaptive strategies
E. Is used repeatedly
3. What implication(s) does the law of conservation of matter have for humans?
A. We cannot create energy because it is neither created nor destroyed
B. As matter is recycled it loses some of its integrity so we need to be careful when we dispose of goods
C. Natural resources are unlimited because they are used and reused by living organisms
D. Disposable goods are not going "away" when we throw them out
E. All of these are implications of the law of conservation of matter
4. Which of the following statements changes the following false statement into a true statement? "Most, but not all, living organisms are made up of organic compounds."
A. All living organisms are made up of organic compounds
B. All living organisms are made up of only inorganic compounds
C. Most, but not all, living organisms are made up of inorganic compounds
D. Most, but not all, living organisms are made up of organic elements
E. Most, but not all, living organisms are made up of inorganic elements
5. A fat or oil is to a _______ as an enzyme is to a _______.
A. Nucleic acid; lipid
B. Protein; nucleic acid
C. Nucleic acid; carbohydrate
D. Carbohydrate; protein
E. Lipid; protein
6. Nucleic acid is to _______ as lipid is to _______.
A. Cellular membrane structure; energy storage
B. Cellulose structure; genetic storage
C. Energy storage; cellulose structure
D. Genetic storage; cellular membran.
An automotive technician is skeptical of published miles/tutorialoutletLeytonz
FOR MORE CLASSES VISIT
tutorialoutletdotcom
An automotive technician is skeptical of published miles -per -gallon figures and thus performs an
experiment to see how fuel -efficient one particular car actually is. The car's mileage recorder is the
dashboard odometer. What should the technician do to obtain the car's correct miles -per -gallon figure?
A. Use the car's owner manual. Obtain the car's fuel tank capacity and record as Y gallons.
Exercise 1 Measurements and the MicroscopesBreak-out Group NuBetseyCalderon89
Exercise 1: Measurements and the Microscopes
Break-out Group Number:
Section:
Student Names (First and Last)
Student Panther ID #s
Johana Rodriguez
6173932
Jason Charles
6123334
jiuyi huang
6126684
iffat mahmood
3994473
_____________________________________________________________________________
OBJECTIVES:
1. Understand measurements and conversions of the metric system.
2. Learn how to properly use both compound and dissecting microscopes.
_____________________________________________________________________________
INTRODUCTION:
Numbers and measurements impact every part of our lives, and are tools that scientists, engineers, astronauts, chefs and doctors use to analyze data, build bridges, fly orbiters into space, adjust recipes, and prescribe medication. Collecting and analyzing data allows us to understand patterns in the natural world that are not easily observed with the naked eye, and the natural variation that is inherent to all organisms is the major reason we need measurements. In today’s lab you will learn about basic measurements and common instruments used by scientists on a daily basis. Your ability to learn and use these concepts will be tested and reinforced throughout the semester.
____________________________________________________________________________
Task 1 - MEASUREMENTS IN SCIENCE: Familiarize yourself with the metric system.
Recall from last week that a key component of the scientific method is experimentation. This step is necessary for the collection of data that will either lend support to, or lead to the rejection of, the hypothesis being tested. In general, data can be qualitative or quantitative. Qualitative data describe variables based on quality (e.g. smell, appearance, texture, etc) and are usually gathered through interviews, pictures, field notes and/or surveys. Quantitative data define the quantity of a variable through measurements (e.g. length, area, cost, height, age, etc.). The main disadvantage of qualitative data is that they are often too subjective (what smells good to one individual might not smell equally well to another). Therefore, quantitative data, which can be statistically manipulated and analyzed, are the preferred choice of most scientists because they provide objective, less biased measures. However, we will examine both types of data in greater detail throughout the semester.
The metric system is used as the international standard to make measurements worldwide. It is based on units of ten (see Table 1 and 2). In contrast, the Imperial Units of Measurement is based on historical precedent, e.g., a foot was first measured as the length of a man’s foot. Because the metric system is widely employed throughout the scientific arena, it will be covered in this lab.
Table 1:
Prefix
Abbreviation
Division or Multiple of Metric Unit
Pico
p
0.000000000001
Nano
n
0.000000001
Micro
µ
0.000001
Milli
m
0.001
Centi
c
0.01
Deci
d
0.1
Base unit
-----
1
Deka
da
10
Hector
h
100
Kilo
k ...
CHAPTER 1 QUESTIONS (32 points total)1. List six environmental .docxsleeperharwell
CHAPTER 1 QUESTIONS: (32 points total)
1. List six environmental dilemmas that we now face and summarize how each concerns us (12 points)
2. What is extreme poverty, and why should we care? (5 points)
3. Why should we be worried about economic growth in China? (5 points)
4. How much would it cost to eliminate acute poverty and ensure basic human needs for everyone? (5 points)
5. Why are indigenous people important as guardians of nature? (5 points)
CHAPTER 2 QUESTIONS: (36 points total)
1. Why are widely accepted, well-defended scientific explanations called “theories”? (5 points)
2. Draw a diagram showing the steps of the scientific method, and explain why each is important. (12 points)
3. What is positive feedback loop? What is a negative feedback loop? Give an example of each. (8 points)
4. Why do we say that proof is elusive in science? (5 points)
5. What is a manipulative experiment? A natural experiment? A controlled study? (6 points)
Matter, Energy, and Life
ENSC 1410
Chapter 3 Quiz
NAME: ______ _____________ Section: _____ Date: _________________
I. MULTIPLE CHOICE (4 points each)
1. How are matter and mass related?
A. Mass is a component of matter
B. Neither matter nor mass take up space
C. Matter is a component of mass
D. Both matter and mass take up space
E. Mass takes up space while matter does not take up space
2. The law of conservation of matter tells us that matter
A. Can never be reused
B. Needs to be conserved or it will not be available for future generations
C. Can be destroyed
D. Can be conserved by some adaptive strategies
E. Is used repeatedly
3. What implication(s) does the law of conservation of matter have for humans?
A. We cannot create energy because it is neither created nor destroyed
B. As matter is recycled it loses some of its integrity so we need to be careful when we dispose of goods
C. Natural resources are unlimited because they are used and reused by living organisms
D. Disposable goods are not going "away" when we throw them out
E. All of these are implications of the law of conservation of matter
4. Which of the following statements changes the following false statement into a true statement? "Most, but not all, living organisms are made up of organic compounds."
A. All living organisms are made up of organic compounds
B. All living organisms are made up of only inorganic compounds
C. Most, but not all, living organisms are made up of inorganic compounds
D. Most, but not all, living organisms are made up of organic elements
E. Most, but not all, living organisms are made up of inorganic elements
5. A fat or oil is to a _______ as an enzyme is to a _______.
A. Nucleic acid; lipid
B. Protein; nucleic acid
C. Nucleic acid; carbohydrate
D. Carbohydrate; protein
E. Lipid; protein
6. Nucleic acid is to _______ as lipid is to _______.
A. Cellular membrane structure; energy storage
B. Cellulose structure; genetic storage
C. Energy storage; cellulose structure
D. Genetic storage; cellular membran.
An automotive technician is skeptical of published miles/tutorialoutletLeytonz
FOR MORE CLASSES VISIT
tutorialoutletdotcom
An automotive technician is skeptical of published miles -per -gallon figures and thus performs an
experiment to see how fuel -efficient one particular car actually is. The car's mileage recorder is the
dashboard odometer. What should the technician do to obtain the car's correct miles -per -gallon figure?
A. Use the car's owner manual. Obtain the car's fuel tank capacity and record as Y gallons.
Exercise 1 Measurements and the MicroscopesBreak-out Group NuBetseyCalderon89
Exercise 1: Measurements and the Microscopes
Break-out Group Number:
Section:
Student Names (First and Last)
Student Panther ID #s
Johana Rodriguez
6173932
Jason Charles
6123334
jiuyi huang
6126684
iffat mahmood
3994473
_____________________________________________________________________________
OBJECTIVES:
1. Understand measurements and conversions of the metric system.
2. Learn how to properly use both compound and dissecting microscopes.
_____________________________________________________________________________
INTRODUCTION:
Numbers and measurements impact every part of our lives, and are tools that scientists, engineers, astronauts, chefs and doctors use to analyze data, build bridges, fly orbiters into space, adjust recipes, and prescribe medication. Collecting and analyzing data allows us to understand patterns in the natural world that are not easily observed with the naked eye, and the natural variation that is inherent to all organisms is the major reason we need measurements. In today’s lab you will learn about basic measurements and common instruments used by scientists on a daily basis. Your ability to learn and use these concepts will be tested and reinforced throughout the semester.
____________________________________________________________________________
Task 1 - MEASUREMENTS IN SCIENCE: Familiarize yourself with the metric system.
Recall from last week that a key component of the scientific method is experimentation. This step is necessary for the collection of data that will either lend support to, or lead to the rejection of, the hypothesis being tested. In general, data can be qualitative or quantitative. Qualitative data describe variables based on quality (e.g. smell, appearance, texture, etc) and are usually gathered through interviews, pictures, field notes and/or surveys. Quantitative data define the quantity of a variable through measurements (e.g. length, area, cost, height, age, etc.). The main disadvantage of qualitative data is that they are often too subjective (what smells good to one individual might not smell equally well to another). Therefore, quantitative data, which can be statistically manipulated and analyzed, are the preferred choice of most scientists because they provide objective, less biased measures. However, we will examine both types of data in greater detail throughout the semester.
The metric system is used as the international standard to make measurements worldwide. It is based on units of ten (see Table 1 and 2). In contrast, the Imperial Units of Measurement is based on historical precedent, e.g., a foot was first measured as the length of a man’s foot. Because the metric system is widely employed throughout the scientific arena, it will be covered in this lab.
Table 1:
Prefix
Abbreviation
Division or Multiple of Metric Unit
Pico
p
0.000000000001
Nano
n
0.000000001
Micro
µ
0.000001
Milli
m
0.001
Centi
c
0.01
Deci
d
0.1
Base unit
-----
1
Deka
da
10
Hector
h
100
Kilo
k ...
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Home assignment II on Spectroscopy 2024 Answers.pdf
Cuestionario nuevo 11
1. FERN
ANDO MULCUE NIETO
LUIS FERNANDO MULCUE NIETO
LUIS FERN
ANDO MULCUE NIETO
LUIS FERNANDO MULCUE NIETO
CURSO PRE-ICFES
¡Prepárate para el camino a la excelencia!
+AMOR+DISCIPLINA +FE+ESPERANZA
CUESTIONARIO NUEVO 11: CIENCIAS (PARTE 2)
NOTA: Algunas de las preguntas de este cuestionario
corresponden las liberadas del Icfes, y son usadas para
propósitos estrictamente académicos.
1. Un motor de gasolina, como el que usan los automóviles,
es una máquina que convierte energía química proveniente
del combustible en energía cinética o de movimiento. Estos
motores tienen una eficiencia del 25%, es decir, por cada 100
Joules de energía, 25 Joules se convierten en energía
cinética; el resto se transforma en otros tipos de energía.
Si el automóvil de la figura viaja en una carretera horizontal,
¿en qué se transforma la mayoría de la energía no utilizada
para mover el automóvil?
A. En energía potencial gravitacional.
B. En energía lumínica (luz).
C. En energía calórica (calor).
D. En energía elástica
2. Un agrónomo estudia el lugar de las condiciones óptimas
para la producción de maíz en una región. El debe medir las
siguientes variables meteorológicas en distintos lugares para
estar seguro de su elección: precipitación, temperatura y la
cantidad de horas de luz solar al día. ¿Cuáles son las
unidades estándar en las que debe registrar los datos de estas
variables?
A. Precipitación en grados centígrados (ºC). Temperatura en
milímetros (mm). Cantidad de horas luz solar al día en
porcentaje (%).
B. Precipitación en horas (h). Temperatura en milímetros
(mm). Cantidad de horas luz solar al día en grados
centígrados(ºC).
C. Precipitación en grados milímetros (mm). Temperatura en
grados centígrados (ºC). Cantidad de horas luz solar al día
en horas (h).
D. Precipitación en milímetros (mm). Temperatura en horas
(h). Cantidad de horas luz solar al día en grados
centígrados (ºC).
3. Un grupo de estudiantes frota dos globos con un paño de
lana (ver figura 1). Después de frotados, se observa que dos
globos se repelen entre ellos (ver figura 2).
Una posible explicación que puede dar el grupo de
estudiantes a lo observado es:
A. Al frotarse con el mismo paño, los globos adquieren cargas
eléctricas de igual signo y, por lo tanto, generan fuerzas
repulsivas.
B. Al frotarse con el mismo paño, los globos adquieren cargas
eléctricas de diferente signo y, por lo tanto, generan
fuerzas repulsivas.
C. La frotación con el paño no altera la carga de los globos,
tienen sus cargas neutras y, por lo tanto, no se genera
fuerza alguna.
D. La frotación con el paño no altera la carga de los globos,
tienen sus cargas neutras y, por lo tanto, generan fuerzas
repulsivas.
4. Un estudiante modela el flujo de calor entre dos objetos (P
y Q), a partir de la analogía con el movimiento del agua
contenida en dos recipientes.
El estudiante observa que cuando se conectan dos recipientes
con niveles y cantidades de agua diferentes (ver figura), el
agua se mueve del recipiente P al recipiente Q, hasta que los
dos recipientes tienen el mismo nivel de agua. En el modelo,
el nivel de líquido representará la temperatura y la cantidad de
líquido representará la energía térmica (que se puede
transferir como calor). Según el modelo, si se colocan los
objetos de diferentes tamaños
(Volumen Q> Volumen P) y temperaturas (Temperatura P>
Temperatura Q), ¿cómo será el flujo de calor?
A. De Q a P, porque fluiría del cuerpo con mayor calor al
cuerpo con menor calor.
B. De P a Q, porque fluiría del cuerpo con mayor temperatura
al cuerpo con menor temperatura.
C. De P a Q, porque fluiría del cuerpo con menor temperatura
al cuerpo con mayor temperatura.
D. De Q a P, porque fluiría del cuerpo con menor calor al
cuerpo con mayor calor.
5. Un grupo de investigadores realizó mediciones de la
temperatura promedio anual en una región, durante 5 años
consecutivos. Se observa un aumento de al menos 1ºC en la
temperatura promedio después del quinto año. El grupo quiere
conocer los fenómenos que causaron este aumento de
temperatura en la región. ¿Cuál de las siguientes preguntas
puede resolverse mediante una investigación, según el campo
de las ciencias naturales?
A. ¿Cuál es el efecto del aumento de la temperatura en las
finanzas del gobierno de la región?
B. ¿Cuál será el partido político beneficiado en las próximas
elecciones debido al aumento de la temperatura?
C. ¿El aumento de la temperatura ha favorecido el
desplazamiento de personas de la región?
D. ¿Ha variado la intensidad de luz emitida por el Sol durante
los últimos 5 años, lo cual causa el aumento de
temperatura?
6. A continuación se presentan dos unidades mediante las
cuales se puede medir la concentración de una disolución:
Un estudiante tiene dos disoluciones de distinta concentración
de una misma sustancia, cuya masa es 200 g por cada mol,
como se muestra a continuación.
Teniendo en cuenta la masa de una mol de la sustancia, ¿son
equivalentes las concentraciones de ambas disoluciones?
2. FERN
ANDO MULCUE NIETO
LUIS FERNANDO MULCUE NIETO
LUIS FERN
ANDO MULCUE NIETO
LUIS FERNANDO MULCUE NIETO
CURSO PRE-ICFES
¡Prepárate para el camino a la excelencia!
+AMOR+DISCIPLINA +FE+ESPERANZA
A. Sí, porque las dos disoluciones tienen un volumen
diferente.
B. Sí, porque de acuerdo con el valor de la masa, 1 mol/L
equivale a 200 g/1000 mL, que sería igual a 20 % p/V.
C. No, porque la cantidad de moles son las mismas en las
dos disoluciones, de manera que la concentración no
cambia.
D. No, porque las disoluciones están preparadas con la
misma sustancia.
7. En átomo Q neutro tiene 13 electrones, 13 protones y 13
neutrones. Este átomo neutro tiene una de las siguientes
configuraciones electrónicas y su ion, la otra:
Configuración I: 1s2
2s2
2p6
3s2
3p1
Configuración II: 1s2
2s2
2p6
Teniendo en cuenta que un ion se forma cuando se carga
eléctricamente de forma positiva o negativa, ¿cuál de las
anteriores configuraciones electrónicas corresponden a un ion
positivo de átomo Q?
A. La configuración I, porque esta configuración tiene 3
electrones más que el átomo Q neutro.
B. La configuración II, porque esta configuración tiene 3
electrones menos que el átomo Q neutro.
C. La configuración II, porque esta configuración tiene 1
protón menos que el átomo Q neutro.
D. La configuración I, porque esta configuración tiene 1
protón más que el átomo Q neutro.
8. En la tabla 1 se presentan dos unidades mediante las
cuales se puede medir la concentración de una sustancia.
TABLA 1
Molaridad (M) Porcentaje peso/volumen (% p/V)
𝑀 =
𝑚𝑜𝑙𝑒𝑠 𝑑𝑒 𝑠𝑜𝑙𝑢𝑡𝑜
1 𝐿 𝑑𝑒 𝑠𝑜𝑙𝑢𝑐𝑖ó𝑛
(% 𝑝/𝑉) =
𝑔𝑟𝑎𝑚𝑜𝑠 𝑑𝑒 𝑠𝑜𝑙𝑢𝑡𝑜
100 𝑚𝐿 𝑑𝑒 𝑠𝑜𝑙𝑣𝑒𝑛𝑡𝑒
𝑋100
Un estudiante tiene dos soluciones (X y Z) de 100 mL de
NaOH (masa molar de 40 g/mol) en agua, como se describe
en la Tabla 2
TABLA 2
Disolución
X Z
Volumen (mL) 100 100
Concentración 1M 40% p/V
Con base en la información anterior, y teniendo en cuenta que
1 Litro = 1000 mL, ¿cuál de las disoluciones tiene mayor
concentración de NaOH?
A. La disolución Z, porque tiene 40 g disueltos en 100 mL,
mientras que la disolución X tiene 4 g disueltos en 100 mL.
B. La disolución Z, porque su concentración molar es de 2M.
C. La disolución X, porque su concentración molar es de
100%p/V.
D. La disolución X, porque tiene 40 g disueltos en 100 mL,
mientras que la disolución Z tiene 4 g disueltos en 100 mL.
9. Los cultivos de una especie frutal de interés económico
para cierta región, están siendo infectados por un hongo que
ataca los tallos y los hace más débiles, impidiendo el
crecimiento de la planta hasta la etapa de producción de
frutos. Para solucionar el problema se consulta a un grupo de
científicos, quienes intentan modificar un conjunto de genes
en esta especie de planta, para volverla resistente a la
infección producida por el hongo. De acuerdo con la situación
planteada, ¿cuál de las siguientes preguntas puede ser
abordada desde las ciencias naturales?
A. ¿La modificación de un grupo de genes potenciará la
producción de sustancias tóxicas en la planta que evitará
la infección producida por el hongo?
B. ¿Qué beneficios económicos le traerá a los agricultores la
manipulación de genes vegetales en el tratamiento de las
enfermedades en sus cultivos?
C. ¿Cómo contribuirá la experimentación con plantas al
desarrollo social y cultural de la región que sufre con la
infección del hongo?
D. ¿Qué otro tipo de actividad o negocio podrán utilizar los
agricultores para reemplazar el cultivo afectado por el
hongo?
10. El salto alto con garrocha es un deporte que consiste en
saltar la mayor altura posible superando un listón, con la
ayuda de una vara; el saltador corre unos metros, clava la vara
en el suelo y se impulsa hasta superar el listón, después de lo
cual suelta la vara y cae sobre una colchoneta, como se
muestra en la figura.
A partir de la información anterior, ¿cuáles transformaciones
de energía se dan en todo el proceso de salto con garrocha?
A. Energía potencial - Energía cinética - Energía potencial.
B. Energía cinética - Energía potencial - Energía cinética.
C. Energía cinética - Energía eléctrica - Energía potencial.
D. Energía potencial - Energía cinética - Energía térmica.