Lecture One - Chapter 1: Framework (States of Matter, Transitions, Sig Figs, Conversions, Substances)

Flashcards covering states of matter, phase transitions, molecular forces, basic unit conversions, significant figures rules, density, and basic definitions of pure substances, elements, compounds, and molecules from the lecture notes.

What are the three fundamental states of matter?

Solid, liquid, and gas.

Which phase transition occurs when a solid changes directly into a gas?

Sublimation.

Which phase transition occurs when a gas changes directly into a solid?

Deposition.

What is the process called when a liquid becomes a solid?

Freezing (solidification).

What is the process called when a solid becomes a liquid?

Melting (fusion).

What is the process called when a liquid becomes a gas?

Vaporization (evaporation/boiling).

What is the process called when a gas becomes a liquid?

Condensation.

What are intramolecular forces and intermolecular forces?

Intramolecular forces hold atoms within a molecule; intermolecular forces hold molecules together.

What do monoatomic, diatomic, and triatomic mean?

Monoatomic = one atom; diatomic = two atoms; triatomic = three atoms.

What is the standard inch-to-centimeter conversion?

1 inch = 2.54 centimeters.

What is the standard foot-to-centimeter conversion?

1 foot = 30.48 centimeters.

What is the standard pound-to-gram conversion?

1 pound = 453.6 grams.

What is the standard gallon-to-liter conversion?

1 gallon ≈ 3.785 liters.

What is the standard mile-to-kilometer conversion?

1 mile ≈ 1.60934 kilometers.

How many cubic centimeters are in one liter?

1 liter = 1000 cubic centimeters.

What is the rule that All nonzero digits are significant?

Nonzero digits are always significant.

What is the rule for leading zeros in significant figures?

Leading zeros are not significant.

What are captive zeros and when are they significant?

Zeros between nonzero digits are significant (captive zeros).

When are trailing zeros significant in sig figs?

Trailing zeros with a decimal point are significant.

Why are trailing zeros without a decimal point sometimes ambiguous in sig figs?

They may represent 2 or 4 significant figures; decimal indicator is needed for clarity.

Do exact numbers have a limited or unlimited number of significant figures?

Exact numbers have unlimited significant figures.

What is the rule for multiplication and division regarding significant figures?

The result has as many significant figures as the least precise factor.

What is the rule for addition and subtraction regarding significant figures?

Round to the least precise decimal place (least precise place value).

What is the formula for density?

d = m / v (density equals mass divided by volume).

If density is 19.3 g/mL and volume is 1 mL, what is the mass?

Mass = 19.3 g.

What is a pure substance?

A substance with a fixed composition that cannot be separated into simpler substances by physical means.

What is an element?

A pure substance consisting of only one type of atom; cannot be decomposed into simpler substances by chemical means.

What is a compound?

A substance composed of two or more elements chemically bonded; can be decomposed by chemical reactions.

What is a molecule?

Two or more atoms chemically bonded to form a discrete unit.

Is ice an element or a compound, and why?

Ice is a compound (H2O) composed of hydrogen and oxygen; it cannot be separated into elements by physical means.

Who are the first elements on the periodic table?

Hydrogen and Helium.

Give an example of a molecule that is a compound and not an element (a common example).

Water (H2O) is a compound made from hydrogen and oxygen.