Chemistry 101 Introductory Chemistry Chapter 1 The Chemical World
Who discovered the law of conservation of mass?
Antoine Lavoisier
Which of the following is considered a hypothesis (as opposed to an observation)?
Birds can fly because they have hollow bones.
The Greek philosophers used observation and experimentation to understand the world.
False
The properties of water do not depend on how the atoms are bonded together in a molecule.
False
Which of the following would be considered a theory?
Helium balloons float because helium is less dense than air.
Which of the following is an example of a scientific law?
In a chemical reaction, matter is neither created nor destroyed.
Who discovered the atomic theory?
John Dalton
Charcoal was burned in a barbecue grill. The ashes that remained weighed considerably less than the charcoal that was burned. Does this mean that the law of conservation of mass is wrong? Explain.
No. The charcoal was burned and turned into a gas causing change to the mass.
A sample of wood with a mass of 3.0 grams was burned in an open dish. The ashes weighed 1.2 grams. What happened to the rest of the wood?
The remaining 1.8 grams was converted into gaseous compounds.
Which statement about the scientific method is TRUE?
The scientific method emphasizes observation and experimentation as the way to understand the world.
Which statement would NOT be an example of "quantification"?
The water in the swimming pool feels colder than it was yesterday.
A scientific law is a brief statement that summarizes past observations and predicts future ones.
True
A scientific theory describes the underlying reasons for observations and laws.
True
A theory can only exist after many experiments have validated a hypothesis.
True
Atoms and molecules determine how matter behaves.
True
Which of the following is an example of an observation?
When a can of soda pop is opened, a fizzing sound is heard.
The key to success in chemistry is:
curiosity mathematical skills commitment practice all of the above
Which of the following items does NOT contain chemicals?
drain cleaner organically grown vegetables air inseticides all of the above contain chemicals
Which of the statements below is NOT part of the scientific method?
observation and measurement formation of a hypothesis testing of a hypothesis by experimentation refinement of a hypothesis as needed all of the above steps are part of the scientific method
A good definition of chemistry is:
the science that seeks to understand what matter does by studying what atoms and molecules do
