Chapter 1 & 2 Notes: Units of Measurement, Energy, and Atomic Theory

A set of practice flashcards covering physical and chemical properties/changes, energy concepts, measurement units, significant figures, and foundational atomic theory. The cards are designed to review key facts appearing in the lecture notes (Ch. 1 and Ch. 2).

What term describes properties that describe a substance without changing its chemical composition (e.g., boiling point)?

Physical properties.

What term describes the characteristic chemical reactions a substance undergoes (e.g., reactivity with oxygen)?

Chemical properties.

Do physical changes alter the chemical composition of a substance?

No.

Do chemical changes involve the conversion of reactants to products?

Yes.

What two energies make up the total energy of an object?

Kinetic energy and potential energy.

What type of energy is associated with an object's position or its chemical bonds?

Potential energy.

What law states that energy is neither created nor destroyed, but transferred from one form to another?

Law of conservation of energy.

Why do hydrocarbons store high potential energy and tend to undergo combustion?

Because their chemical bonds store high potential energy that decreases when they react.

What is the SI unit for length?

Meter (m).

What is the SI base unit for mass?

Kilogram (kg).

What is the SI base unit for time?

Second (s).

What is the SI base unit for temperature?

Kelvin (K).

What is the SI base unit for amount of substance?

Mole (mol).

What is the SI base unit for electric current?

Ampere (A).

What is the SI base unit for luminous intensity?

Candela (cd).

What does SI stand for?

International System of Units.

What SI prefix corresponds to 10^3?

Kilo (k).

What SI prefix corresponds to 10^6?

Mega (M).

What is the derived unit for volume?

Cubic meter (m^3).

What is the derived unit for speed?

Meter per second (m/s).

What is the derived unit for density?

Kilogram per cubic meter (kg/m^3).

What is the derived unit for frequency?

Hertz (Hz) = s^-1.

What is the derived unit for force?

Newton (N) = kg·m/s^2.

Are interior zeros significant?

Yes; interior zeros are significant.

Are leading zeros significant?

No; leading zeros are not significant.

What rule applies to significant figures when adding or subtracting numbers?

The result has the same number of decimal places as the quantity with the fewest decimal places.

What rule applies to significant figures when multiplying or dividing numbers?

The result has the same number of significant figures as the factor with the fewest significant figures.

What happens to significant figures when you take the logarithm of a number?

The mantissa (digits after the decimal) reflects the significant figures of the original number.

What is an isotope?

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

What is an ion?

A charged species formed when an atom gains or loses electrons.

What is a cation?

A positively charged ion formed when an atom loses electrons.

What is an anion?

A negatively charged ion formed when an atom gains electrons.

What is Avogadro's number?

6.022 × 10^23 per mole.

What is a unified atomic mass unit (u)?

1/12 the mass of a carbon-12 atom.

Where are protons confined in an atom?

In the nucleus.

Where are neutrons confined in an atom?

In the nucleus.

What is the elementary charge of an electron?

-1.60218 × 10^-19 coulombs.

What is the approximate mass of an electron?

9.10938 × 10^-31 kilograms.

What did Rutherford's gold foil experiment reveal about atomic structure?

Most of the atom's mass and positive charge are in a tiny nucleus; most of the atom is empty space.

What did Dalton's Atomic Theory state as the first postulate?

Elements are composed of tiny, indestructible particles called atoms.