Exam 1 Review Chemistry Flashcards

Vocabulary flashcards generated from the exam review lecture slides covering types of matter, energy, significant figures, dimensional analysis, measurement precision/accuracy, density, atomic structure, periodic trends, and mole calculations.

Oxygen Gas ($O_2$)

An example of an element composed entirely of a single type of atom.

Normal Saline ($NaCl$ in $H_2O$)

An example of a mixture formed by dissolving sodium chloride in water.

Table Sugar ($C_{12}H_{22}O_{11}$)

An example of a solid chemical compound.

Solid State

The state of matter that is most likely the result of taking away a large amount of energy.

Gas State

The highest-energy state of matter among solids, liquids, gases, and fluids.

Number $0.0007000$

A number containing exactly four significant figures, where the leading zeros are non-significant and the three trailing zeros after the 7 are significant.

Number $0.04050$

A numerical value containing leading zeros ($0.0$), a captive zero (between 4 and 5), and a trailing zero (after 5).

Significant Figures in Subtraction ($3.182 - 81$)

A calculation rule where the final result ($-78$) must match the measurement with the fewest decimal places (0 decimal places), giving 2 significant figures.

Significant Figures in Multiplication with Trailing Decimal Point ($300. \times 9$)

A calculation where $300.$ has 3 significant figures due to the decimal point and $9$ has 1 significant figure, resulting in an answer rounded to 1 significant figure.

Significant Figures in Multiplication without Decimal Point ($300 \times 9$)

A calculation where $300$ has 1 significant figure and $9$ has 1 significant figure, resulting in an answer rounded to 1 significant figure.

Intermediate Step Significant Figures ($2.18 - \frac{10.0}{3.0}$)

The first step ($\frac{10.0}{3.0}$) results in 1 decimal place and 2 significant figures ($3.3$), which determines the precision carried into the next operation.

Currency Conversion Rate ($\text{USD}$ to $\text{JPY}$)

At an exchange rate of $1\text{ USD} = 160.19\text{ JPY}$, purchasing with \text{US}\text{\\$500} yields $80095\text{ JPY}$ rounded to the nearest whole number.

Effective Radiation Dose Calculation

Calculated by multiplying exposure rate ($0.004\text{ mSv}\text{ s}^{-1}$) by exposure time ($2.5\text{ s}$), giving a total dose of $0.010\text{ mSv}$ ($1.0 \times 10^{-2}\text{ mSv}$) expressed to 2 significant figures.

Annual Occupational Radiation Exposure

The total yearly dosage calculated from an average of $0.250\text{ mSv}$ per month over 12 months, resulting in $3.00\text{ mSv}$, which is below the $20.0\text{ mSv}$ per year occupational limit.

Fluoride Consumption Calculation

Determining mass by multiplying fluid concentration ($0.70\text{ mg}\text{ L}^{-1}$) by total volume ($2 \times 1183\text{ mL} = 2.366\text{ L}$), resulting in $1.68\text{ mg}$ of fluoride.

Instrumental Precision of Centimeter Ruler

Because the ruler has markings every $0.1\text{ cm}$, measurements must be estimated to the hundredths place ($0.01\text{ cm}$); values recorded only to the tenths or ones place (such as $0.2\text{ cm}$ or $10\text{ cm}$) are unacceptable.

Estimated Volume Reading ($1\text{ mL}$ Increments)

For a medicine cup marked every $1\text{ mL}$, a liquid level slightly less than halfway between $7\text{ mL}$ and $8\text{ mL}$ is recorded as $7.3\text{ mL}$ by estimating one decimal digit beyond the marked divisions.

High Precision with Unknown Accuracy

A dataset where measurements ($23.8\text{ cm}$, $23.6\text{ cm}$, $23.8\text{ cm}$, $23.9\text{ cm}$) are closely grouped together, but accuracy cannot be determined without a true reference value.

Low Accuracy with High Precision

A dataset where measured values ($11.87\text{ mL}$, $11.88\text{ mL}$, $11.86\text{ mL}$, $11.87\text{ mL}$, $11.89\text{ mL}$) are closely clustered near each other but significantly differ from the true literature value of $10.00\text{ mL}$.

Dental Amalgam Mass Calculation

Calculated by multiplying density ($11.00\text{ g}\text{ cm}^{-3}$) by volume ($0.02200\text{ cm}^3$), yielding $0.2420\text{ g}$ or $242.0\text{ mg}$.

Density and Mass Comparison

When comparing equal volumes of materials, the material with the lowest density (dental porcelain at $2.05\text{ g}\text{ cm}^{-3}$, versus zirconia at $6.1\text{ g}\text{ cm}^{-3}$ and cobalt-chromium alloy at $8.5\text{ g}\text{ cm}^{-3}$) will have the lightest mass.

Fluorine-17 ($^{17}\text{F}$)

The isotope among carbon-14, nitrogen-15, oxygen-16, and fluorine-17 that contains the largest number of protons ($9$ protons).

Most Common Isotope of Iron

Iron-56 ($^{56}_{26}\text{Fe}$), inferred from iron's average atomic mass of approximately $55.85\text{ amu}$.

Cobalt Ion ($^{59}_{27}\text{Co}^{2+}$)

A atomic ion containing $27$ protons, $32$ neutrons ($59 - 27$), and $25$ electrons ($27 - 2$).

Boron ($\text{B}$)

An element on the periodic table classified as a metalloid.

1st Period Metal

An impossible periodic classification, as the first period contains only nonmetal elements (hydrogen and helium).

Iodine ($\text{I}$) vs. Strontium ($\text{Sr}$) Periodic Trends

Iodine is heavier than strontium due to its greater atomic mass, but smaller in atomic radius due to higher effective nuclear charge across the same period.

Electron Affinity Trend

Nonmetal elements like oxygen ($\text{O}$) are the most likely to gain electrons to form anions compared to metals.

Molar Mass of Magnesium Sulfate ($ ext{MgSO}_4$)

The total molar mass calculated from one magnesium, one sulfur, and four oxygen atoms, equal to $120.4\text{ g}\text{ mol}^{-1}$.

Moles of Water in $1.000\text{ kg}$

Calculated by dividing $1000.\text{ g}$ of $\text{H}_2\text{O}$ by its molar mass ($18.015\text{ g}\text{ mol}^{-1}$), yielding $55.51\text{ mol}$ expressed to 4 significant figures.

Mass of Iron(III) Oxide ($ ext{Fe}_2 ext{O}_3$)

Calculated by multiplying $0.1029\text{ mol}$ of iron(III) oxide by its molar mass ($159.69\text{ g}\text{ mol}^{-1}$), yielding $16.43\text{ g}$.