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