Scientific Graphing, Atomic Structure, and Matter & Change

Comprehensive practice flashcards covering scientific graphing techniques, atomic charges and periodic table basics, and the classification, properties, and changes of matter.

What is the primary function of a line graph, and along which axes are the variables plotted?

A line graph compares two variables, with the independent variable placed along the horizontal ($x$-axis) and the dependent variable placed along the vertical ($y$-axis).

What is the difference between interpolation and extrapolation when reading a line graph?

Interpolation is making predictions within recorded data points, whereas extrapolation is making predictions about data that has not yet been recorded.

How do independent and dependent variables differ in a controlled experiment?

The independent variable is the factor varied and specifically controlled by the experimenter (plotted on the $x$-axis), while the dependent variable is the factor measured that changes as a result of the independent variable (plotted on the $y$-axis).

What rules must be followed when setting up the scale of a line graph?

Determine the numeric magnitude of each variable, establish a scale that best fits the range, ensure consistency across each axis, and spread the graph to utilize at least $\frac{3}{4}$ of the available space.

What is the conventional format for writing a scientific line graph title?

Graph titles are written at the top in the format: $''\text{Y-axis variable}'' \text{ vs. } ''\text{X-axis variable}''$.

What type of relationship between variables is displayed in this graph?

An indirect relationship, meaning that as one variable increases, the other variable decreases.

What specific characteristic does this peak-line graph illustrate regarding enzyme activity?

It shows an optimum, where activity peaks at a maximum value (near $37\,^\circ\text{C}$ to $40\,^\circ\text{C}$) before declining.

In dendrochronology studies, what do thin and thick annual tree rings indicate about developmental conditions?

A thin ring indicates a rough developmental period (such as lack of water, insect infestation, or forest fires), while a thick ring indicates a prosperous period.

Based on clam development data across temperatures from $15\,^\circ\text{C}$ to $50\,^\circ\text{C}$, what is the optimum water temperature for development?

$30\,^\circ\text{C}$, which yields the highest development count of $140$ clams.

What are the three main subatomic particles of an atom and their electric charges?

Protons have a positive charge ($+$), electrons have a negative charge ($-$), and neutrons have no charge ($0$).

What fundamental rule determines whether two electrical charges attract or repel?

Opposite charges attract, and like charges repel.

What does an element's atomic number indicate, and what defines a neutral atom?

The atomic number indicates the number of protons in an atom; in a neutral atom, the number of protons equals the number of electrons.

How does an atom acquire a net electrical charge?

An atom becomes positively charged by losing electrons and negatively charged by gaining electrons.

If an atom has $11$ protons and loses $1$ electron from an initial neutral state of $11$ electrons, what is its resulting charge?

It has a charge of $+1$ because it now possesses $11$ protons and $10$ electrons.

What is the difference between intensive and extensive properties of matter?

Extensive properties depend on the amount of matter present (e.g., mass, volume, length), whereas intensive properties depend only on the type of matter, not the amount (e.g., density, melting point, color).

How do solids, liquids, and gases compare regarding definite shape, definite volume, and compressibility?

Solids have a definite shape, definite volume, and are not easily compressed; liquids have an indefinite shape, definite volume, and are not easily compressed; gases have an indefinite shape, indefinite volume, and are easily compressed.

A rock has a mass of $127\,g$ and displaces $32.1\,mL$ of water. What is the density of the rock?

$3.97\,g/mL$, calculated as $\text{Density} = \frac{\text{Mass}}{\text{Volume}} = \frac{127\,g}{32.1\,mL}$.

A metal bar weighs $57.3\,g$ and has a volume of $4.7\,mL$. If pure gold has a density of $19.32\,g/mL$, is the metal bar pure gold?

No, because the density of the metal bar is $\frac{57.3\,g}{4.7\,mL} \approx 12.19\,g/mL$, which is significantly lower than $19.32\,g/mL$.

Balloons containing hydrogen ($0.0899\,g/L$), helium ($0.1785\,g/L$), and carbon dioxide ($1.977\,g/L$) are released into air ($1.29\,g/L$). Which balloon floats the highest?

The hydrogen balloon, because hydrogen has the lowest density ($0.0899\,g/L$), providing the greatest buoyant difference relative to air.

What distinguishes a physical change from a chemical change?

A physical change alters the form or appearance of a material without producing a new substance, whereas a chemical change transforms a substance into one or more chemically different substances.

Does this model represent a physical or chemical change?

A chemical change, because the chemical bonds between shapes have broken and rearranged to form entirely new particle combinations.

What does the Law of Conservation of Mass state regarding a chemical reaction?

The mass of the reactants must equal the mass of the products, as matter is neither created nor destroyed during a chemical reaction.

If $22.99\,g$ of sodium ($Na$) reacts completely with $35.45\,g$ of chlorine ($Cl_2$), what mass of sodium chloride ($NaCl$) forms?

$58.44\,g$ of $NaCl$, according to the Law of Conservation of Mass ($22.99\,g + 35.45\,g = 58.44\,g$).

When $400\,g$ of wood burns and leaves only $30\,g$ of ash, where did the missing $370\,g$ of matter go?

The missing $370\,g$ of matter was released into the surrounding air as smoke and gaseous products, such as carbon dioxide and water vapor.

What is the fundamental difference between an element and a compound?

An element is a pure substance composed of only one kind of atom that cannot be separated into simpler substances, while a compound consists of two or more elements chemically combined in fixed ratios.

How do homogeneous mixtures differ from heterogeneous mixtures?

A homogeneous mixture has a uniform composition throughout and consists of a single phase, while a heterogeneous mixture has a non-uniform composition with two or more distinct phases.

How can a mixture containing sand, salt, and water be separated into each of its individual components?

First, use filtration to separate the undissolved sand from the saltwater solution; second, use distillation or evaporation to separate the water from the dissolved salt.

What is the primary difference in operational principle between filtration and distillation?

Filtration separates undissolved solids from liquids based on particle size, while distillation separates homogeneous liquid solutions based on differences in boiling points.