Chemistry: An Atoms-First Approach - Chapter 1 (Sections 1.1–1.6)

A set of practice flashcards covering key concepts from Section 1.1 to 1.6 of Zumdahl's Chemistry: An Atoms First Approach.

Why is studying atoms important?

Understanding atoms provides insight into macroscopic structures and their behavior, the formation of molecules, attraction between molecules, and helps solve many chemistry-related problems.

Approximately how many different types of atoms exist?

About 100 different types of atoms.

What determines the properties of a substance?

The arrangement of its atoms.

What is an atom?

The smallest part of an element that is still that element.

What is a molecule?

Two or more atoms joined and acting as a unit.

What are diatomic molecules?

Chemical elements that naturally possess two atoms.

What defines a chemical reaction?

One substance changes to another by reorganizing the way the atoms are attached to each other.

What is the scientific method?

A framework for gaining and organizing knowledge, a plan of action, and a procedure for processing information; it varies with the problem.

What is a scientific model (theory)?

A set of tested hypotheses that explains a natural phenomenon, often including observations and interpretations.

What is a natural law?

An observation that applies to many different systems.

What does the Law of conservation of mass state?

Mass is neither created nor destroyed in a chemical change.

What is the Law of definite proportions?

A given compound always contains exactly the same proportion of elements by mass.

Dalton's atomic theory: What is stated about elements?

Elements are made up of tiny particles called atoms.

Dalton's atomic theory: Are atoms of a given element identical?

Yes, they are identical.

Dalton's atomic theory: Do atoms of different elements differ?

Yes, in fundamental ways.

Dalton's atomic theory: How are compounds formed?

When atoms of different elements combine with each other.

Dalton's atomic theory: Does a given compound have the same relative numbers and types of atoms?

Yes, it always has the same relative numbers and types of atoms.

What happens to atoms during chemical reactions?

Atoms are rearranged; the atoms themselves are not changed.

Who prepared the first table of atomic masses?

Dalton.

What does Avogadro's hypothesis state?

At the same temperature and pressure, equal volumes of different gases contain the same number of particles.

What did J.J. Thomson determine about the electron?

The charge-to-mass ratio (e/m) of the electron, showing cathode rays are electrons.

What is the charge-to-mass ratio of the electron?

e/m = -1.76 × 10^8 C/g.

What is the Plum Pudding model?

A model in which atoms are composed of a positively charged cloud with embedded electrons.

What did Millikan measure in his experiments?

The magnitude of the electron's charge and the mass of the electron (9.11 × 10^-31 kg).

What is radioactivity and what are its emissions?

Radioactivity is spontaneous emission; the emissions include gamma rays (γ), beta particles (β), and alpha particles (α).

What did Rutherford discover about the nucleus?

A highly concentrated center of positive charge (the nucleus) within the atom.

In the modern view, where are protons, neutrons, and electrons located?

Protons and neutrons are in the nucleus; electrons orbit outside the nucleus.

Where is most of an atom's mass located?

In the (very small) nucleus.

What determines an atom's chemical properties?

The number and arrangement of electrons.

What are isotopes?

Atoms with the same number of protons (same Z) but different numbers of neutrons.

What is the atomic number Z?

The number of protons in the nucleus.

What is the mass number A?

The total number of protons and neutrons in the nucleus.

In isotope notation 23/11 Na, what do 23 and 11 represent?

23 is the mass number A; 11 is the atomic number Z.

What is an isotope symbol with Z and A used to show?

It shows the number of protons (Z) and the total number of protons plus neutrons (A).

What is an ion?

An atom with a net charge due to adding or removing electrons.

What is a cation?

A positively charged ion (electrons removed).

What is an anion?

A negatively charged ion (electrons added).

What does the fluorine-19 isotope notation 19/9 F tell you about protons, electrons, and neutrons?

9 protons, 9 electrons (to be neutral), and 10 neutrons (19 - 9 = 10).