Which of these statements BEST explains why chemistry is flexible?
It is biased
It adds new evidence
It cannot be reproduced
It cannot be verified
Which of the following questions can be answered by science?
What is the purpose of our existence on earth?
Should students be allowed to bring toys to school?
Should the driving age be reduced?
What is the composition of air?
Which of the following is the unit of length in the metric system?
Meter
Foot
Inch
Mile
A car travels at a speed of 80 km/h. Which of the following is correct to convert the speed of the car to hm/s? (1 km = 10 hm, 1 hr = 3600 s)
Divide 80 by 3,600
Multiply 80 by 3,600
Divide 80 by 10 and multiply the results obtained by 3,600
Multiply 80 by 10 and divide the result obtained by 3,600
Which of the following types of energy does an object have because of its position?
Potential
Kinetic
Radiant
Sound
Which of the following shows examples of things that convert light energy into electrical energy?
Fan and wind turbine
Light bulb and blender
Solar panels and solar cells
Airplane and human body
The atoms and molecules in a gas are in constant motion. Temperature is a measure of this motion. How are these related?
As temperature decreases, the molecules and atoms move farther apart.
As temperature increases, the molecules and atoms move faster
As temperature decreases, the molecules and atoms move faster
As temperature increases, the molecules and atoms move farther apart
The table compares the characteristics of a substance in three different states of matter. Which of these BEST describes the state of the substance represented by state Y?
It is a solid because there is negligible attraction between particles
It is a liquid because there is negligible attraction between particles
It is a liquid because the particles of the substance have higher speeds
It is a gas because the particles of the substance have the highest speeds
The following properties are either physical or chemical. Which one is different from the rest based on those two categories?
Flammability
Thermal Conductivity
Magnetism
Boiling Point
Which of the following could result from a substance that undergoes a physical change?
It undergoes phase change
It changes irreversibly
Its elemental composition is altered
Its atoms rearrange to form a new molecule
What type of change occurs when an iron bar rusts?
Chemical change
It is reversible
It cannot be reversed
Physical change
Rust is the formation of a new substance
Rust is part of the metal and not a new substance
What type of change occurs when a substance freezes?
Phase changes
Composition changes
Can revert back to its original form
Cannot revert back to its original form
Which of the following is a property of a pure substance?
Its components can be separated by applying physical methods
It consists of different types of compounds
It is made up of a single element or type of compound
It may have substances in different states of matter
The gas carbon dioxide is a pure substance. Which of the following is true about carbon dioxide?
Carbon and oxygen are chemically bonded in it.
The portion of carbon and oxygen is different in different samples of gas.
Carbon and oxygen retain their original identity in it.
It can be separated into carbon and oxygen using physical methods.
A student compares the boiling point of substances having different intermolecular forces. Which independent variable did the student most likely use?
Boiling points of various substances
Type of source used to heat up the substances
Type of container used for the substances
The intermolecular forces of various substances
Which of the following is an example of using creativity while trying to explore scientific questions?
Using accurate and precise measurements
Thinking of various research projects
Using trial-and-error methods
Selecting appropriate lab equipment
A balance scale is used to weigh a 2.233 g sample of copper sulfate. Which of these measurements made is the most accurate?
2.2 g
2.1 g
2.5 g
2.4 g
Which statement explains which thermometer is more appropriate to measure the temperature of a liquid at 43.6 degrees Celsius?
Thermometer A, because it measures temperature more accurately than Thermometer B
Thermometer B, because it measures temperature more precisely than Thermometer A
Thermometer A, because it measures temperature more precisely than Thermometer B
Thermometer B, because it measures temperature more accurately than Thermometer A
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