Chem Final

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Which of the following elements are in the same period as magnesium (Mg)? A. Mn B. Cl C. Sr D. Ca E. None of the above

B. Cl

Which statement is most accurate? A. Science focuses on the development of new technology B. New technologies arise from scientific discoveries C. The goal of technology is the development of new science D. Technology and science are basically the same

B. New technologies arise from scientific discoveries

If an element has 15 protons and 16 neutrons and 15 electrons, what is the atomic mass of the element?

31

How many atoms of Oxygen (O) are in HClO4?

4

If an oxygen has the following chemical symbol, how many electrons does it have? 18O6

6

How many atoms are in one molecule of Na2SO4?

7

If someone is able to explain an idea to you using small familiar words, what does this say about how well that person understands the idea?

A person who completely understands an idea is capable of explaining it using language that is familiar to both of you

The following statement describes which subatomic particles best? It has a relatively large mass

A proton and neutron

If one meter is equal to 39.4 inches, how many centimeters are in one foot A. 30.5 cm B. 0.305 cm C. 472 cm D. 4.72 cm E. 305 cm

A. 30.5 cm

The estimated average daily requirement of folic acid for pregnant females is 520 micrograms. Which answer accurately expresses this value? A. 520 hg B. 520 mg C. 520 Mg

A. 520 hg

What determines the direction of heat flow? A. Heat always flows from a higher-temperature substance into a lower-temperature substance. B. The direction of heat flow is not predictable in any given process. C. Heat always flows from a lower-temperature substance into a higher-temperature substance. D. Heat flow direction depends upon the density of the substances involved.

A. Heat always flows from a higher-temperature substance into a lower-temperature substance

Which of the following best describes a liquid? A. a constant volume but its shape is not defined B. will always expand to fill the full volume of its container. C. a constant shape and a constant volume D. does not have a definite shape or a definite volume E. does not deform upon application of pressure

A. a constant volume but its shape is not define

Which of the following is a metalloid? A. antimony (atomic no. = 51) B. uranium (atomic no. = 92) C. zinc (atomic no. = 30) D. sulfur (atomic no. = 16) E. iodine (atomic no. = 53)

A. antimony (atomic no. = 51)

Since mass is usually expressed in grams and volume in mL or cc (1 mL = 1 cm3 = 1 cc), density is often expressed in g/mL. We can calculate density using the formula A. density = mass/volume B. density = mass x volume C. density = mass - volume D. density = volume/mass E. density = mass + volume

A. density = mass/volume

What is the first step in the scientific process A. observe a natural phenomenon B. generate a scientific hypothesis C. check results by repeating work D. develop a test E. make a prediction about what may be happening

A. observe a natural phenomenon

How might you separate a mixture of sand and salt? A. two of these answers are reasonable. B. heat the mixture until one of the components melts C. with tweezers and a magnifying glass D. just add water

A. two of these answers are reasonable

Which of the following has the largest density? A. a 200-g object with a volume of 200 mL B. a 10-g object with a volume of 1 mL C. a 10-g object with a volume of 10 mL D. All of the densities are the same. E. a 1-g object with a volume of 10 mL

B. a 10-g object with a volume of 1 mL

Most scientific inquires begin with ________. A. a theory B. a strong interest C. mathematics formula

B. a strong interest

Dmitri Mendeleev ________. A. developed the basis of our modern periodic table B. all of these C. predicted the existence of elements not yet discovered D. helped in the discovery of missing elements by predicting their behavior

B. all of these

Any technology ________ A. should have no risks before being used B. has some risks C. has a very high risk causing certain types of cancer D. only has risks when being used without care

B. has some risks

Which of the following would not be considered matter A. rain B. idea C. air D. trees E. clouds

B. idea

Any conversion factor is equal to ________ A. the negative of its inversion factor B. one C. the new unit being derived D. its reciprocal

B. one

It is true that ________ A. technology has nothing to do with the problems in society B. technology needs to be used responsibly by people and societies as a whole C. technology is always helpful D. technology is the source of most all society's problems, such as pollution and cancer

B. technology needs to be used responsibly by people and societies as a whole

Which of the following does not describe volume? A. a box 20 cm x 20 cm x 20 cm B. the weight of a given object C. milliters D. the amount of space a material occupies E. liters

B. the weight of a given object

Which of the following is an example of a physical change? A. water being electrolyzed and being converted in hydrogen and oxygen B. water boiling and being converted into steam C. iron metal reacting with oxygen to form rust D. a candy bar being digested by a student E. charcoal being converted into ash

B. water boiling and being converted into steam

What is your weight in kilograms if you weigh 155 pounds? (1 kg = 2.2 lbs) A. 34.1 kg B. 341 kg C. 70.5 kg D. 3.41 kg E. 7.5 kg

C. 70.5 kg

What is the mass in grams of 85.32 mL of blood plasma with a density of 1.03 g/mL? Round your answer to the proper number of significant figures A. 87.88g B. 82.83g C. 87.9g D. 82.8g E. 85.32g

C. 87.9g

Distinguish between a scientific hypothesis and a theory A. A scientific hypothesis must be testable, while a theory has already been tested B. Once a scientific hypothesis has been proven to be accurate, it becomes known as a theory C. A scientific hypothesis is a testable assumption, while a theory is a well-verified idea used to explain a broad range of phenomena D. In order to be scientific, an hypothesis must be backed by a theory E. Only a scientific hypothesis is subject to scrutiny, while a theory is generally accepted to be true and thus does not change

C. A scientific hypothesis is a testable assumption, while a theory is a well-verified idea used to explain a broad range of phenomena

Which of the following elements are in the same group as silicon (Si)? A. None of the above B. B C. C D. As E. P

C. C

Which element is a noble gas? A. N B. Ra C. Kr D. More than one of the posted is a noble gas E. H

C. Kr

Which of the following would be considered a chemical property? A. melting temperature B. conductivity C. boiling temperature D. reactivity towards water E. flexibility

D. reactivity towards water

Which of the following would be considered a heterogeneous mixture? A. vegetable oil B. vinegar C. water D. salad dressing E. milk

D. salad dressing

Which of these is not a metal? A. potassium (atomic no. = 19) B. gallium (atomic no. = 31) C. vanadium (atomic no. = 23) D. selenium (atomic no. = 34) E. lithium (atomic no. = 3)

D. selenium (atomic no. = 35)

With increasing temperature the density of air ________.

Depends also on pressure

If a piece of rock that has a volume of 0.73 L and a mass of 1524 g, what is the density of the rock in g/mL? A. 20.9 g/mL B. 2.1 x 10^3 g/mL C. 4.8 x 10^-4 g/mL D. 0.48 g/mL E. 2.1 g/mL

E. 2.1 g/mL

Which of the following would be considered a physical property? A. reactivity towards acid B. flammability C. oxygen sensation D. corrosion resistance E. density

E. density

What type of phase change does the following figure best describe? (Box with objects at the bottom) & (Box with objects moving all around) A. melting B. condensation C. freezing D. none of these E. evaporation

E. evaporation

How would you describe the volume of the following object? the amount of water in a swimming pool A. microscopic B. submicroscopic C. all of these D. none of these E. macroscopic

E. macroscopic

An example of basic research is ________ A. the development of new plastics that can be recycled B. the study of the relationship between the amount of automobile emissions gases in the atmosphere and the decomposition of atmospheric ozone C. the study of natural compounds in sea animals to look for new molecules that can be used for medicine D. the design of new batteries for electric cars E. the study of the composition of the atom

E. the study of the composition of the atom

Which of the scientific activities is likely to be most time consuming?

Experimentation is the most time consuming of the various scientific acitivites

Which element has the atomic number 9?

F

8mL is larger than 8 dL True or False

False

Isotopes are atoms of the same element having a different number of protons True or False

False

The measurement 10.3 cm has more significant figures than the measurement 10.3 m. True or Flase

False

Rank the following by the relative amounts of energy, from most energetic to least:

Gamma rays, blue light, red light, radio waves

How would you classify the following material? swimming pool water

Homogeneous mixture

When water freezes, it expands. What does this say about the density of ice compared with the density of water?

Ice is less dense than water because it has more volume for the same mass.

If the density of mercury is 13.6 g/mL and the density of lead is 11.3 g/mL, which has the larger volume: 1 g of mercury or 1 g of lead?

Lead

Give the correct symbol for the element: Manganese

Mn

How many electrons are there in the third shell of sodium, Na (atomic number 11)?

One

What is the difference between radiation and electromagnetic radiation?

Radiation is from decay of nuclei while electromagnetic radiation is any form of light.

Which element is a transition metal in period 4?

Sc

In which are the molecules moving faster: a swimming pool of boiling water or a cup of boiling water?

The average motion of the molecules is the same

What is the difference between a compound and a mixture?

The components of a mixture are not chemically bonded together.

The base unit for volume in the metric system is liter (L). True or False

True

The chemical symbol for manganese is 'Mn.'

True

The density of a substance has units of g/mL. True or False

True

Which would you rather have: a decigram or a kilogram of gold?

a kilogram of gold because this is 10,000 times as much as a decigram of gold

Why do aerosol cans explode if heated?

An increase in temperature will increase the pressure inside the aerosol can. When the pressure inside the can exceeds the pressure limit of the can, it explodes.

The boiling point of methanol is 65°C and the boiling point of ethanol is 78°C. What would happen to the gas and liquid?

At 70°C you would have methanol gas and liquid ethanol.

Which of the following represents the largest quantity of mass? A. 24 micrograms B. 24 kilograms C. 24 grams D. 24 milligrams E. 24 nanograms

B. 24 kilograms

102,000 mL represent ___ significant figures A. 2 B. 3 C. 6 D. 5

B. 3

Which atom is smallest? A. Mg B. Be C. Ca D. Sr E. All are the same size

B. Be

What is the name of the following compound? SF3

sulfur trifluoride

When a liquid evaporates, the vapor expands because ________.

the gas particles have more kinetic energy than the liquid particles

The ray of light within a neon sign bends when a magnet is held up to it because ________.

the light arises from the flow of electron within the tube

Based on experimental evidence, John Dalton postulated that ________.

each element consists of indivisible, minute particles called atoms

A substance that cannot be broken down into chemically simpler components is a(n):

element

When blue food coloring is dissolved in water, the result is a ________.

homogeneous mixture called a solution

How would you describe the size of the following object? a blood cell

microscopic

The atomic symbol for cobalt is ________.

Co

What property describes a metal?

Conducts heat very well

Which of the following is the least amount of energy? A. 1.0 calorie B. 1.0 kilocalorie C. 1.0 Calorie D. 1.0 joules E. 1.0 kilojoule

D. 1.0 joules

Measurement of 0.0101 g represents ____ significant figures A. 2 B. 4 C. 5 D. 3

D. 3

Which number contains four significant figures? A. 1700 B. 0.780 C. 0.0086 D. 3.978

D. 3.978

The recommended dietary allowance for calcium for teenage children is 1,300 mg per day. If a typical 8.0-fl oz glass of reduced-fat milk contains 298 mg of calcium, how many fluid ounces of milk does a teenager need to drink to get the entire recommended amount of calcium from this milk? A. 1.8 fl oz B. 3.5 fl oz C. 32 fl oz D. 35 fl oz C. 4.4 fl oz

D. 35 fl oz

Which of the following statements about electrons is true? A. Electrons are particles B. Electrons have a negative charge C. Electrons in atoms can be excited by light energy D. All of these E. Electrons behave like waves

D. All of these

Is chemistry the study of the submicroscopic, the microscopic, or the macroscopic, or all three A. Macroscopic because it deals with powders, liquids, and gases that fill beakers and flasks B. Submicroscopic because it deals with atoms and molecules, which can't be seen with a microscope C. Microscopic because it pertains to the formation of crystals D. All of these because most everything is made of atoms and molecules

D. All of these because most everything is made of atoms and molecules

Which of the following statements is false? A. An atomic spectrum is an element's fingerprint B. Light that is high in energy has a high frequency C. The atomic spectrum of helium is different from the atomic spectrum of neon D. An atom emits electromagnetic radiation when an electron moves from a lower energy to a higher energy level E. Electromagnetic radiation often behaves like a wave

D. An atom emits electromagnetic radiation when an electron moves from a lower energy to a higher energy level

Compared to microtechnology, nanotechnology focuses on a scale that is about ________.

1000 times smaller

If a neutral element has 8 neutrons and 7 electrons, which expression correctly identifies the element?

15N7

Phosphorous-32 is used for organ imaging. How many neutrons are in this radioisotope?

17

An atom of the isotope chlorine-37 consists of how many protons, neutrons, and electrons?

17p, 20n, 17e

A piece of aluminum weighing 10.0 grams is placed into a graduated cylinder that has an initial volume (before immersion) of 35.0 mL. After immersion, the volume on the cylinder reads 38.7 mL. What is the density of the metal sample?

2.70 g/mL

When did modern science begin? A. With Galileo's falling rock experiments in Pisa, Italy B. Upon the discovery of the wheel of inquiry C. When people first became skeptical of their observations and explanations. D. With the greatly respected Greek philosopher Aristotle.

C. When people first became skeptical of their observations and explanations

Which would have the most kinetic energy? The same mass of ________. A. a solid B. a cool liquid C. a hot gas D. a hot liquid E. a cool gas

C. a hot gas

Chemistry is the study of ________ A. only macroscopic phenomena B. matter C. both matter and transformation D. only microscopic phenomena

C. both matter and transformation

Which of the following is not a property of an electron? A. fundamental components of atoms B. attracted towards positively charge electrical plates C. charge changes depending on mass D. weighs approximately 9.1 × 10-31 kg E. has a negative charge

C. charge changes depending on mass

A scientific law _________ natural phenomenon and a theory ___________ natural phenomenon A. explains, explains B. verifies, describes C. describes, explains D. describes, verifies

C. describes, explains

A scientific hypothesis is a ______________ A. theory being tested B. prediction of what might happen in a certain situation C. testable explanation D. restatement of an observation

C. testable explanation

Why is reproducibility such a vital component of science A. Modern scientific procedures provide built-in assurances so that reproducibility is no longer considered to be a vital component of science. B. Reproducibility allows a scientist a second chance to show that his/her initial findings were correct C. Reproducibility is a vital component of science because it provides repeat funding D. An experiment can only be considered valid if other scientists can reproduce the results

D. An experiment can only be considered valid if other scientists can reproduce the results

Which of the following gases would diffuse the fastest through an extremely fine membrane? A. Ne B. Xe C. All of these would diffuse at the same rate D. He E. Ar

D. He

What do all conversion factors have in common A. Each conversion factor is actually different, so they have nothing in common B. They are universal constants C. They all have units of mass, volume, distance, and weight D. They are all equal 1, because the value of the numerator is always equal to the value of the denominator.

D. They are all equal 1, because the value of the numerator is always equal to the value of the denominator

Which of the following best describes a theory A. a prediction about the outcome of an experiment B. a new way of testing an old idea C. a static, unchanging law of the universe D. a comprehensive idea that has been extensively tested

D. a comprehensive idea that has been extensively tested

Any measurement of a physical quantity must always include two things: ____________ A. a prefix and a suffix of the unit B. documentation and confirmation C. an instrument and an observer D. a numerical value and a proper unit

D. a numerical value and a proper unit

Which of the following is a mixture?

air

Based on the Law of Mass Conservation, Lavoisier hypothesized that ________.

an element is made of a fundamental substance that cannot be broken down into anything else

According to John Dalton, atoms of a given element ________

are similar

What is the name of the following compound? CaCl2

calcium chloride

What is the name of the following compound? CO2

carbon dioxide


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