Chemistry
HW - Chapter 1
Due:
1. Scientific Theory
Part A
Which is true about scientific theories?
ANSWER:
a theory is a model that explains the underlying reasons for observations and scientific laws
a theory briefly summarizes past observations and predicts future ones
a theory is a scientific opinion with very little observations to support it
a theory is a method of learning that emphasizes reason as the way to understand the world
none of the other answers apply
2. Exercise 1.17
Classify each of the following as an observation, a law, or a theory.
Part A - When a metal is burned in a closed container, the mass of the container and its contents do not change.
ANSWER:
theory
observation
law
Part B - Matter is made of atoms.
ANSWER:
theory
law
observation
Part C - Matter is conserved in chemical reactions.
ANSWER:
law
theory
observation
Part D - When wood is burned in a closed container, its mass does not change.
ANSWER:
observation
law
theory
3. Exercise 1.5
Part A - Define chemistry.
ANSWER:
Chemistry is the science that seeks to understand what matter does by studying what atoms and molecules do.
Chemistry is the science of matter and its motion, as well as space and time - the science that deals with concepts such as force, energy, mass, and charge.
Chemistry is the science that studies the molecular transformations only in nonliving matter.
Chemistry is the science that studies the molecular transformations only in living matter.
4. Exercise 1.12
Part A - What is the law of conservation of mass?
ANSWER:
In a chemical reaction, matter is neither created nor destroyed.
In a chemical reaction, matter is created and destroyed.
In a chemical reaction number of atoms remains constant.
In a chemical reaction energy remains constant but cannot be recreated, although it may change forms.
Part B - Who discovered it?
ANSWER:
Antoine Lavoisier
Amedeo
Due:
1. Scientific Theory
Part A
Which is true about scientific theories?
ANSWER:
a theory is a model that explains the underlying reasons for observations and scientific laws
a theory briefly summarizes past observations and predicts future ones
a theory is a scientific opinion with very little observations to support it
a theory is a method of learning that emphasizes reason as the way to understand the world
none of the other answers apply
2. Exercise 1.17
Classify each of the following as an observation, a law, or a theory.
Part A - When a metal is burned in a closed container, the mass of the container and its contents do not change.
ANSWER:
theory
observation
law
Part B - Matter is made of atoms.
ANSWER:
theory
law
observation
Part C - Matter is conserved in chemical reactions.
ANSWER:
law
theory
observation
Part D - When wood is burned in a closed container, its mass does not change.
ANSWER:
observation
law
theory
3. Exercise 1.5
Part A - Define chemistry.
ANSWER:
Chemistry is the science that seeks to understand what matter does by studying what atoms and molecules do.
Chemistry is the science of matter and its motion, as well as space and time - the science that deals with concepts such as force, energy, mass, and charge.
Chemistry is the science that studies the molecular transformations only in nonliving matter.
Chemistry is the science that studies the molecular transformations only in living matter.
4. Exercise 1.12
Part A - What is the law of conservation of mass?
ANSWER:
In a chemical reaction, matter is neither created nor destroyed.
In a chemical reaction, matter is created and destroyed.
In a chemical reaction number of atoms remains constant.
In a chemical reaction energy remains constant but cannot be recreated, although it may change forms.
Part B - Who discovered it?
ANSWER:
Antoine Lavoisier
Amedeo