Chapter 1: Matter, Measurement, and Problem Solving

Practice flashcards covering matter classification, SI units, significant figures, precision and accuracy, dimensional analysis, and data interpretation from Chapter 1.

How is chemistry defined in Chapter 1 of the text?

Chemistry is the science that seeks to understand the behavior of matter by studying the behavior of atoms and molecules.

What are the shape and volume characteristics of solids, liquids, and gases?

Solids have a definite shape and a definite volume; liquids have no definite shape but a definite volume; gases have no definite shape and no definite volume.

What is the difference between an element and a compound?

An element is a pure substance made up of only one kind of atom, whereas a compound is formed when two or more different elements are chemically bonded together in a definite proportion.

How many elements have scientists identified?

Scientists have identified $118$ elements.

What is the difference between a pure substance and a mixture?

A pure substance contains only one kind of matter (a pure element or pure compound), while a mixture consists of two or more substances physically combined without being chemically bonded.

What French phrase does the abbreviation SI come from?

Système International d’ Unités.

What are the seven SI base units and their corresponding symbols?

Length: meter ($m$); Mass: kilogram ($kg$); Time: second ($s$); Temperature: Kelvin ($K$); Amount of substance: mole ($mol$); Electric current: Ampere ($A$); Luminous intensity: candela ($cd$).

What are the four parts of every measured number?

Sign (positive or negative value), Quantity (amount measured), Uncertainty (error produced from device), and Unit (nature of quantity measured).

How are leading zeroes treated when counting significant figures?

Leading zeroes are never significant; they are merely decimal placeholders to show the position of the decimal point.

Under what conditions are trailing zeroes considered significant?

Trailing zeroes are significant if they follow nonzero digits and are to the right of a decimal point. Trailing zeroes in numbers with no decimal point are not significant.

How is significant figure precision determined when adding or subtracting measurements?

The answer is limited by the value with the highest uncertainty, which corresponds to the least number of digits after the decimal point.

How is significant figure precision determined when multiplying or dividing measurements?

The answer is limited by the measurement with the fewest significant figures.

How is the measurement $151\,mL$ rounded off to two significant figures?

$150\,mL$ (using a placeholder zero).

What are the metric prefixes and multipliers for $10^6$, $10^{-3}$, $10^{-6}$, and $10^{-9}$?

Mega ($M$) is $10^6$, milli ($m$) is $0.001$ ($10^{-3}$), micro ($\mu$) is $0.000001$ ($10^{-6}$), and nano ($n$) is $0.000000001$ ($10^{-9}$).

What is the exact standard English-to-metric conversion for length involving inches and centimeters?

$1\,in = 2.54\,cm$ (exact).

What is the difference between mass and weight?

Mass is the quantity of matter present in an object and is not affected by gravity, whereas weight is the force that gravity exerts on an object and varies with gravitational field strength.

How is density defined, and what are its common units?

Density is defined as the mass of a substance per unit volume ($\text{Density} = \frac{\text{mass}}{\text{volume}}$), and its common units are $\text{g/cm}^3$ or $\text{g/mL}$.

How do accuracy and precision differ in scientific measurements?

Accuracy refers to how close a measured value is to the actual value, whereas precision refers to how close a series of measurements are to one another.

What is the difference between random error and systematic error?

Random error is an error that has an equal probability of being too high or too low, whereas systematic error is an error that tends toward being either too high or too low.

What is dimensional analysis?

Dimensional analysis is an approach that uses units as a guide to solving unit conversion and chemical problems.

How must a conversion factor be constructed when converting units raised to a power?

Both the number and the unit in the conversion factor must be raised to that power, such as $(2.54\,cm)^2 = (1\,in)^2 \rightarrow 6.45\,cm^2 = 1\,in^2$.

When water decomposes into hydrogen and oxygen, what is the ratio of oxygen mass to hydrogen mass?

The ratio of oxygen mass to hydrogen mass is approximately $8$.

According to carbon dioxide climate data presented in the text, around what year did the rate of increase intensify?

The rate of increase intensified since about 1960.