Which of the following best describes an example of pure chemistry? A. testing the effects of lower concentrations of a drug on humans. B. studying chemicals containing carbon C. developing a cure for osteoporosis d. finding an antidote for a new strain of virus
B. studying chemicals containing carbon.
Which of the following statements are false? A. knowledge of chemistry allows the public to make informed decisions. B. Studying chemistry ensures that officials make correct choices in funding technology. C. Knowledge of chemistry helps prepare people for careers in soil science. D. Chemistry explains many aspects of nature.
B. Studying chemistry ensures that officials make correct choices in funding technology.
Which of the following can be observed only in a microscopic view? A.foam insulation B. X-ray of a knee joint C. shape of a soybean plant D. structure of a muscle cell
D. structure of a muscle cell
One characteristic of scientific theory is that ____. A. it can never be proved. B. it can be proved. C. it cannot be modified. D. it summarizes a set of observations.
A. it can never be proved.
Which step in the scientific method requires you to use your senses to obtain information? A. revising a hypothesis B. designing an experiment C. making an observation D. stating a theory
C. making an observation
Which of these steps should always be followed for effective problem solving?? A. buying a larger quantity of material than estimated. B. performing metric conversions. C. developing a plan and then implementing the plan D. using a trial-and-error approach and then evaluating
C. developing a plan and then implementing the plan
A golf ball has more mass than a tennis ball because it ______. A. takes up more space B. contains more matter C. contains different kinds of matter D. has a definite composition
B. contains more matter
An example of an extensive property of matter is _______. A. temperature B. pressure C. mass D. hardness
All of the following are physical properties of matter EXCEPT ______. A. mass B. color C. melting point D. ability to rust
D. ability to rust
Which of the following is NOT a physical property of water? A. It has a boiling point of 100C. B. It is a colorless liquid. C. It is composed of hydrogen and oxygen. D. Sugar dissolves in it.
C. It is composed of hydrogen and oxygen.
Which of the following are considered physical properties of a substance? A. color and odor B. melting and boiling points C. malleability and hardness D. all of the above
D. all of the above
A vapor is which state of matter? A. solid B. liquid C. gas D. all of the above
A substance that forms a vapor is generally in what physical state at room temperature? A. solid B. liquid C. gas D. liquid or solid
D. liquid or solid
Which state of matter takes both the shape and volume of its container? A. solid B. liquid C. gas D. both b and c
D. both b and c
Which state of matter is characterized by having an indefinite shape, but a definite volume? A. gas B. liquid C. solid D. none of the above
Which state of matter is characterized by having an definite shape and a definite volume? A. gas B. liquid C. solid D. all of the above
Which state of matter expands when heated and is easy to compress? A. gas B. liquid C. solid D. all of the above
All of the following are physical properties of a substance in the liquid state EXCEPT ______. A. indefinite volume B. definite mass C. not easily compressed D. indefinite shape
A. indefinite volume
Which of the following CANNOT be classified as a substance? A. table salt B. air C. nitrogen D. gold
Which of the following CANNOT be considered a single phase? A. a pure solid B. a pure liquid C. a homogeneous mixture D. a heterogeneous mixture
D. a heterogeneous mixture
Which of the following is true about homogeneous mixtures? A. They are known as solutions. B. They consist of two or more phases. C. They have compositions that never vary. D. They are always liquids.
A. They are known as solutions.
Which of the following is heterogeneous mixture? A. vinegar in water B. milk C. oil and vinegar D. air
C. oil and vinegar
Which of the following is a homogeneous mixture? A. salt water B. beef stew C. sand and water D. soil
A. salt water
Which of the following items is NOT a compound? A. baking soda B. salad dressing C. sucrose D. table salt
B. salad dressing
Which of the following is true about compounds? A. They can be physically separated into their component elements. B. They have compositions that vary. C. They are substances. D. They have properties similar to those of their component.
C. They are substances.
Which of the following materials is a substance? A. air B. gasoline C. stainless steel D.silver
What is one difference between a mixture and a compound? A. A compound consists of more than one phase. B. A compound can only be separated into its components by chemical means. C. A mixture can only be separated into its components by chemical means. D. A mixture must be uniform in composition.
B. A compound can only be separated into its components by chemical means.
What distinguishes a substance from a mixture? A. Substances are compounds, and mixtures are not. B. Mixtures are groupings of elements, and compounds are not. C. Samples of the same substance can have different intensive properties. D. Mixtures can be separated physically, while compounds cannot.
D. Mixtures can be separated physically, while compounds cannot.
Which of the following is used for chemical symbols today? A. drawings B. icons C. letters D. numbers
The chemical formula of a compound does NOT indicate the _____. A. identity of the elements in the compound B. how elements are joined in the compound C. the composition of the compound D. relative proportions of the elements in the compound
B. how elements are joined in the compound
Which substance has a chemical symbol that is derived from a Latin name? A. calcium B. hydrogen C. oxygen D. potassium
Which of the following is a chemical property? A. color B. hardness C. freezing point D. ability to react with oxygen
D. ability to react with oxygen
What must occur for a change to be a chemical reaction? A. There must be a change in chemical properties. B. There must be a change in physical properties. C. The change must involve a change in mass. D. The change must involve a change in volume.
A. There must be a change in chemical properties.
All of the following changes to a metal are physical changes EXCEPT ________. A. bending B. melting C. rusting D. polishing
Which of the following processes does NOT involve a change in chemical properties? A. rusting B. fermenting C. boiling D. burning
What must be done to be certain that a chemical change has taken place? A. Check for the production of bubbles before and after the change. B. Demonstrate that a release of energy occurred after the change. C. Check the composition of the sample before and after the change. D. Demonstrate that energy was absorbed by the reactants after the charge.
C. Check the composition of the sample before and after the change.
When paper turns yellow-brown upon exposure to sunlight, what type of change is likely taking place? A. a physical change B. a chemical change C. neither a physical change nor a chemical change D. both a physical change and a chemical change
B. a chemical change
Which of the following indicates that a chemical change has happened during cooking? A. The food darkens. B. Bubbles form in boiling water. C. Butter melts. D. Energy is transferred from the stove to a pan.
A. The food darkens.
Which of the following does NOT indicate that a chemical change may have taken placE? A. fracture formation B. gas production C. precipitate formation D. energy transfer
A. fracture formation
Which action changes the identity of the substance referenced? A. melting gold B. running an electric current through copper C. corroding iron D. breaking an ice cube
C. corroding iron
The diameter of a carbon atom is 0.000000000154m. What is this number expressed in scientific notation? A. 1.54x10^12m B. 1.54x10^-12m C. 1.54x10^10m D. 1.54x10^-10m
What is the result of multiplying 2.5x10^10 by 3.5 x10^-7?
Which of the following measurements contains two significant figures? A. 0.00400L B.0.00404L C.0.00044L D. 0.00440L
When a test instrument is calibrated, does its accuracy, precision, or reliability improve? A. precision B. accuracy C. reliability D. all of the above
Which of the following measurements (of different masses) is the accurate? A. 3.1000g B. 3.100000g C. 3.12222g D. 3.000000g
Which group of measurements is the most precise? (Each group of measurements is for a different object.) A. 2g, 3g, 4g B. 2.0g, 3.0g, 4.0g C. 2g, 2.5g, 3g D. 1g, 3g, 5g
C. 2g, 2.5g, 3g
Three different people weigh a standard mass of 2.00g on the same balance. Each person obtains a reading of 7.32g for the mass of the standard. These results imply that the balance that was used is ________. A. accurate B. precise C. accurate and precise D. neither accurate nor precise
Which of the following measurements is expressed to three significant figures? A. 0.007m B. 7077mg C. 7.30x10^-7km d. 0.070mm
In the measurements 0.503L, which digit is the estimated digit? A. 5 B. the 0 immediately to the left of the 3 C. 3 D. the 0 to the left of the decimal point
How many significant figures are in the measurement 0.0034kg? A. two B.four C. five D. this cannot be determined.
How many significant figures are in the measurement 811.40 grams? A. two B. three C.four D.five
Which of the following units is NOT an official SI unit? A. kilgram B. Ampere C. mole D. liter
Which of the following volumes is the smallest? A. one microliter B. one liter C. one milliliter D. one deciliter
A. one microliter
What is the temperature of absolute zero measure in °C? A. -373°C B. -273°C C. 273°C D. 373°C
What is the boiling point of water in kelvins? A. 0 K B. 100 K C. 273 K D. 373 K
D. 373 K
Which of the following mass units is the largest? A. 1cg B. 1dg C. 1mg D. 1ng
What is the temperature -34°C expressed in kelvins? A. 139 K B. 207 K C. 239 K D. 339 K
C. 239 K
If the temperature changes by 100 K, by how much does it change in °C? A. 0 °C B. 37 °C C. 100 °C D. 273 °C
C. 100 °C
Chlorine boils at 239K. What is the coiling point of chlorine expressed in degrees Celsius? A. 93°C B. 34°C C. -61°C D. -34°C
A cubic meter is about the same as the volume occupied by a ________. A. kilogram of water B. cup of milk C. washing machine D. basketball arena
C. washing machine
Density is found by dividing ________. A. mass by volume B. volume by mass C. mass by area D. area by mass
A. mass by volume
Who was the man who lived from 460B.C.-370B.C. and was among the first to suggest the idea of atoms? A. Atomos B. Dalton C. Democritus D. Thomson
Which of the following was NOT among Democritus's ideas? A. Matter consists of tiny particles called atoms. B. Atoms are indivisible. C. Atoms retain their identity in a chemical reaction. D. Atoms are indestructible.
C. Atoms retain their identity in a chemical reaction.
Dalton's atomic theory included which idea? A. All atoms of all elements are the same size. B. Atoms of different elements always combine in one-to-one ratios. C. Atoms of the same element are always identical. D. Individual atoms can be seen with a microscope.
C. Atoms of the same element are always identical.
Which of the following is NOT a part of Dalton's atomic theory? A. All elements are composed of atoms. B. Atoms are always in motion. C. Atoms of the same element are identical. D. Atoms that combine do so in simple whole-number ratios.