AnswersPA-Physical Science ACumulative Exam

Cumulative Exam — Cumulative exam Answers

25 verified answers2 views
1
Free Preview

Vincent graduated from college with a degree in horticulture and now owns a local plant nursery. He maintains a blog titled, "How to Live a Happy Life,” and writes that people can lead happier lives by varying the routes they usually take home from work.

A
This claim is scientific because it is based on Vincent’s personal experience.
B
This claim is scientific because other people have taken his advice and are now happier.
C
This claim may not be accurate because the blog is produced by someone who is not an expert in the field of human psychology.
D
This claim may not be accurate because most people follow the same route home.
2
Free Preview

Atoms of arsenic (As) are often added to silicon (Si) in a process called doping to change the conductivity of the silicon. How does the addition of arsenic change the conductivity of silicon?

A
An atom of arsenic has one fewer valence electron and more electron shells than an atom of silicon, so the conductivity decreases because the arsenic atom gains an electron.
B
An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity decreases because the arsenic atom loses the electron.
C
An atom of arsenic has one fewer valence electron and fewer electron shells than an atom of silicon, so the conductivity increases because the arsenic atom gains an electron.
D
An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity increases because the arsenic atom loses the electron.
3

Nio conducts a science experiment. He puts yeast into a bottle with water and sugar, and then caps the bottle with a balloon. He returns two hours later and notices there are bubbles on the surface of the mixture in the bottle and that the balloon has inflated, but there are no other apparent changes.

A
a non-chemical change, because there are no indicators of chemical changes taking place
B
a chemical change, because the mixture changed color
C
a chemical change, because a gas was produced
D
a non-chemical change, because the changes that occurred are reversible
4

Consider the reaction below.2Al2O3 4Al + 3O2How many moles of oxygen are produced if 11.0 mol of Al are produced?

Question illustration
A
8.25 mol
B
11.0 mol
C
14.7 mol
D
16.5 mol
5

Read the passage about the fluoridation of drinking water.Since the early 1960s, fluoride has been added to many sources of drinking water to prevent cavities in teeth. This is called fluoridation. There are some who say that this is unnecessary and increases the risk of cancer.In 1993, the Subcommittee on Health Effects of Ingested Fluoride of the National Research Council, part of the National Academy of Sciences, conducted an extensive study about the link between fluoridated drinking water and increased cancer risk. The study included data from more than 50 human disease studies and six animal studies. The Subcommittee concluded that none of the data showed a link between fluoridated drinking water and cancer. A 1999 report by the CDC supported these findings. The CDC report concluded that studies so far have produced "no credible evidence” of a link between fluoridated drinking water and an increased risk for cancer.

A
There is no link between fluoride exposure and increased cancer risk in humans.
B
There is a possible link between fluoride exposure and increased cancer risk in humans.
C
There is a definite link between fluoride exposure and increased cancer risk in humans and animals.
D
There is a possible link between fluoride exposure and increased cancer risk in animals.
6

How many atoms of each element are in the chemical formula NH4NO3?

A
1 nitrogen, 1 hydrogen, and 3 oxygen
B
1 nitrogen, 4 hydrogen, and 3 oxygen
C
2 nitrogen, 4 hydrogen, and 3 oxygen
D
5 nitrogen, 1 hydrogen, and 1 oxygen
7

Which property of physical changes explains why matter is conserved in a physical change?

A
The arrangements of particles do not change, and the bonds between atoms do not break.
B
Mass, not energy, changes in a physical change.
C
Energy and mass change in a physical change.
D
The bonds between atoms do not break; it is only the arrangement that changes.
8

Calcium, magnesium, and strontium are near each other on the periodic table and have some characteristics in common, but they differ in chemical reactivity. Which lists these metals in order from most reactive to least reactive?

A
calcium, magnesium, strontium
B
magnesium, calcium, strontium
C
strontium, calcium, magnesium
D
strontium, magnesium, calcium
9

Gerard lives in a tropical region where the average annual temperature is 77°F and the average annual rainfall is more than 100 inches a year. He surveys 25 people in his neighborhood about items they regularly use and records the data into a table.

Question illustration
A
umbrellas
B
insulated gloves
C
raincoats
D
rubber boots
10

What does the chemical formula C3H6O2 tell about a molecule of the compound it represents?

A
It is made up of 3 atoms of 11 different elements.
B
It is made up of 11 atoms joined in a straight line.
C
It is made up of 11 total atoms of 3 different elements.
D
It is made up of 1 atom composed of 3 different elements.
11

best

T
The atoms in hydrogen peroxide are breaking apart and forming new types of molecules.
T
The atoms in hydrogen peroxide are breaking apart and recombining into the original molecules.
T
The molecules of hydrogen peroxide remain intact as new types of molecules form and move out of the liquid.
T
The molecules of hydrogen peroxide remain intact but move more quickly to allow evaporation.
12

Consider the equation below.Zn + H2SO4 ZnSO4 + H2The mole ratio of zinc to zinc sulfate is

Question illustration
A
1:1.
B
1:2.
C
2:1.
D
3:1.
13

Lars is balancing equations with his study group. He is unsure about one equation because each member of the study group came up with a different answer. Which is the proper way to balance the equation Ca(OH)2 + H3PO4 → Ca3(PO4)2 + H2O?

A
Ca(OH)2 + H3PO4 → Ca3(PO4)2 + 6H2O
B
3Ca(OH)2 + 2H3PO4 → Ca3(PO4)2 + 6H2O
C
3Ca(OH)2 + 2H3PO4 → Ca3(PO4)2 + 3H2O
D
Ca(OH)2 + 2H3PO4 → Ca3(PO4)2 + 6H2O
14

Which important change in electronic devices, such as televisions and computers, is a result of the use of metalloids as semiconductors?

A
Electronic devices have become smaller.
B
Electronic devices are now more brittle.
C
Electronic devices now use more energy.
D
Electronic devices have become more expensive.
15

Marco wants to investigate the chemical properties of sodium bicarbonate, or baking soda. He plans to carry out the tests below.Test 1: Mix a teaspoon of sodium bicarbonate into a cup of warm water to see if it dissolves.Test 2: Mix a teaspoon of sodium bicarbonate into a cup of vinegar to see if it fizzes.Test 3: Heat a teaspoon of sodium bicarbonate in the oven to see if its melting point is less than 400 degrees Fahrenheit.

O
Only Test 3 will indicate a chemical property of sodium bicarbonate. Tests 1 and 2 will show a physical property of the substance.
O
Only tests 1 and 2 will indicate chemical properties of sodium bicarbonate. Test 3 will show a physical property of the substance.
O
Only Test 2 will indicate a chemical property of sodium bicarbonate. Tests 1 and 3 will show a physical property of the substance.
O
Only tests 1 and 3 will indicate chemical properties of sodium bicarbonate. Test 2 will show a physical property of the substance.
16

Which is the only element in group 1 on the periodic table that forms covalent bonds?

A
hydrogen
B
lithium
C
potassium
D
sodium
17

Students are completing a table about a particular subatomic particle that helps make up an atom.What best explains how they should complete the table?

Question illustration
A
with “Inside the nucleus,” because the particle is a proton
B
with “Inside the nucleus,” because the particle is a neutron
C
with “Outside the nucleus,” because the particle is a proton
D
with “Outside the nucleus,” because the particle is an electron
18

Which is one reason why hydrogen is considered a better fuel source for cars?

A
It is nonrenewable.
B
It produces carbon dioxide.
C
It emits no harmful emissions.
D
It combines with water to produce electricity.
19

Four students are analyzing four different substances and recording their findings in this table.Which most describes this table?

Question illustration
A
Leonna has a solid, Xiao and Blake have liquids, and Amir has a gas.
B
Leonna and Amir have gasses, Xiao has a liquid, and Blake has a solid.
C
Leonna has a solid, Xiao has a liquid, Blake has a gas, and Amir made a mistake.
D
Leonna has a solid, Xiao has a liquid, Blake made a mistake, and Amir has a gas.
20

Students are studying the changing concentration of carbon dioxide levels in different substances. They insert sensors into each substance and allow a device to graph the results.What are the students most likely using?

A
thermometers
B
microscopes
C
probeware
D
silverware

Did you find these answers helpful?

More from this Course

Quiz
50 verified answers

Cumulative Exam