AP Chemistry: Chemical Foundations, Units, and Matter Classification

What is chemistry defined as?

The study of matter and energy and the changes between them.

What are the two components of a quantitative observation?

A number and a unit.

What is the significance of the Scientific Method in chemistry?

It provides a structured approach to experimentation and problem-solving.

What does Boyle's Gas Law state?

P1V1 = P2V2, relating pressure and volume of a gas.

What is the Law of Conservation of Mass?

Mass of reactants equals mass of products.

What is the Law of Conservation of Energy?

Energy cannot be created or destroyed, only changed in form.

Who is known as the 'father of modern chemistry'?

Antoine Lavoisier.

What did Robert Boyle contribute to chemistry?

He created the first vacuum pump and defined elements as substances that cannot be broken down further.

What is the SI system?

An international system of units established in 1960 for better communication in scientific measurements.

What is the relationship between volume and mass in water at 4ºC?

1 cm³ of water equals 1 mL and 1 gram.

How is mass defined in chemistry?

A measure of the resistance of an object to a change in its state of motion.

How is weight defined in chemistry?

The response of mass to gravity, measured in Newtons.

What happens to gravity as altitude increases on Earth?

Gravity decreases as you move further from the center of the Earth.

What is the difference between mass and weight?

Mass is the quantity of matter, while weight is the force exerted by gravity on that mass.

What is a model in scientific terms?

A representation used to explain natural phenomena, which can change with new evidence.

Why is good experimental design important?

It ensures that only one variable is changed at a time, allowing for clear conclusions.

What historical event forced Galileo to recant his observations?

Strong religious resistance to his astronomical findings.

What is the significance of the term 'inertia' in chemistry?

It describes an object's resistance to changes in its state of motion.

What is the metric equivalent of 1 liter in cubic decimeters?

1 dm³.

What is the relationship between decimeters and meters?

1 decimeter is 1/10 of a meter.

What does the term 'reversible reactions' refer to?

Reactions that can proceed in both forward and reverse directions.

What is the impact of politics on scientific progress as mentioned in the notes?

Scientists can face challenges such as misinterpretations, emotional attachments, and political affiliations.

What is the role of models in scientific theories?

Models help explain theories and can be adjusted as new evidence emerges.

What causes astronauts to feel weightless in space?

They are far from the center of Earth, experiencing microgravity, but are still attracted to the ship due to its mass.

How does the gravitational field strength on the Moon compare to that on Earth?

The Moon has 1/6 the mass of Earth, so you would weigh 1/6 of what you weigh on Earth.

What is the difference between accuracy and precision?

Accuracy refers to correctness or agreement with the true value, while precision refers to the reproducibility or degree of agreement among several measurements.

What type of error is characterized by equal probability of a measurement being high or low?

Random or indeterminate error.

What type of error occurs in the same direction each time?

Systematic or determinate error.

In the context of the graduated cylinder experiment, why is the graduated cylinder deemed inaccurate?

It shows a systematic error, likely indicating that the graduated cylinder is flawed.

What are the conditions under which a zero is considered significant?

A zero is significant if it is terminating and to the right of the decimal, or if it is sandwiched between two significant figures.

How many significant figures are in the measurement 0.0105 g?

There are 3 significant figures.

How many significant figures are in the measurement 0.050080 g?

There are 5 significant figures.

How many significant figures are in the measurement 8.050 × 10^-3 s?

There are 4 significant figures.

What determines the number of significant figures in the result of a multiplication or division calculation?

The term with the least number of significant figures determines the maximum number of significant figures in the answer.

What determines the number of decimal places in the result of an addition or subtraction calculation?

The term with the least number of decimal places determines the number of decimal places in the final answer.

What is the significance of the number of significant figures in pH reporting?

The number of significant figures in the least accurate measurement determines the number of decimal places in the reported pH.

What does it mean if a measurement is 'neither precise nor accurate'?

It indicates large random errors with no agreement to the true value.

What does it mean if a measurement is 'precise but not accurate'?

It indicates small random errors but large systematic errors.

What does it mean if a measurement is 'both precise and accurate'?

It indicates small random errors and no systematic errors.

What is the significance of significant figures in scientific measurements?

They indicate the precision of a measurement and help communicate the reliability of the data.

What should you do with numbers during calculations until the end?

Keep the numbers in your calculator and round only at the end.

How do you round the number 7.348 to 2 significant figures?

The number is reported as 7.3.

What is the purpose of using conversion factors in dimensional analysis?

Conversion factors allow you to cancel undesirable units and convert measurements into desired units.

If a straight pin measures 2.85 cm, what is its length in inches?

The length is 1.12 inches.

How do you convert 7.00 inches to centimeters?

Use the conversion factor 2.54 cm = 1 inch.

What size should you order for a bicycle frame that is 25.5 inches, when sizes are given in centimeters?

Convert 25.5 inches to centimeters using the conversion factor.

How do you convert a 10.0-km run into miles?

Use the conversion factors: 1 km = 1000 m, 1 m = 1.094 yd, and 1760 yd = 1 mi.

What is the speed limit of 55 mi/h in kilometers per hour?

Convert using the appropriate conversion factor.

How do you convert a fuel economy of 15 km/L to miles per gallon?

Use the conversion factors for kilometers to miles and liters to gallons.

What are the boiling and freezing points of water in Fahrenheit and Celsius?

Water boils at 212°F (100°C) and freezes at 32°F (0°C).

What is the relationship between temperature changes on the Celsius scale and the Kelvin scale?

A degree of temperature change on the Celsius scale represents the same quantity of change on the Kelvin scale.

How is density calculated?

Density is calculated as mass divided by volume.

What is the density of a substance with a mass of 19.625 g and a volume of 25.00 cm³?

The density is 0.785 g/cm³.

What are the three states of matter?

Solid, liquid, and gas.

What characterizes a solid?

A solid has a definite shape and volume with molecules close together.

What characterizes a liquid?

A liquid has a definite volume but takes the shape of its container, with molecules that can slide past one another.

What characterizes a gas?

A gas has no definite volume and takes the shape of its container, with molecules that are far apart and independent.

What is a vapor?

A vapor is the gas phase of a substance that is normally a solid or liquid at room temperature.

What is the difference between homogeneous and heterogeneous mixtures?

Homogeneous mixtures have visibly indistinguishable parts, while heterogeneous mixtures have visibly distinguishable parts.

What are some means of physical separation for mixtures?

Filtering, fractional crystallization, distillation, and chromatography.

What is electrolysis?

Electrolysis is a chemical method for separating compounds into elements.

What are pure substances?

Pure substances include compounds like water and carbon dioxide, and elements.

What can elements be broken down into?

Elements can be broken down into atoms, which can further be divided into nuclei and electrons.

What are the fundamental particles of an atom?

Protons (p+), neutrons (n0), and electrons (e-).

What are quarks?

Quarks are the fundamental constituents of protons and neutrons.

mega

M 1,000,000

kilo

k 1,000

hecto

h 100

deka

d 10

deci

d 0.1

centi

c 0.01

milli

m 0.001

micro

mu 0.000001

nano

n 0.000000001

What temperature is room temperature?

68 F, 20 C