Chemistry Formulas and Gas Laws Flashcards

Practice question-and-answer flashcards covering key quantum mechanics, stoichiometry, and gas law equations and concepts.

What is the Planck relation using frequency?

$$E = hf$$

What is the Planck relation using wavelength?

$$E = \frac{hc}{\lambda}$$

What is the energy of an electron in the Bohr model?

$$E = -\frac{R_H}{n^2}$$

What is the maximum number of electrons in an electron shell?

$$2n^2$$

What is the maximum number of electrons in a subshell?

$$4\ell + 2$$

How do you calculate moles from mass?

$$\text{moles} = \frac{\text{mass}}{\text{molar mass}}$$

What is the equation for Gram equivalent weight (GEW)?

$$\text{GEW} = \frac{\text{molar mass}}{n}$$

How do you calculate equivalents from mass?

$$\text{equivalents} = \frac{\text{mass}}{\text{GEW}}$$

How do you calculate Molarity from normality?

$$M = \frac{\text{Normality}}{n}$$

What is the percent composition equation?

$$\%\,\text{composition} = \left(\frac{\text{mass of element}}{\text{molar mass}}\right) \times 100\%$$

What is the percent yield equation?

$$\%\,\text{yield} = \left(\frac{\text{actual yield}}{\text{theoretical yield}}\right) \times 100\%$$

What is the Ideal gas law equation?

$$PV = nRT$$

What is the gas density equation using molar mass?

$$\rho = \frac{PM}{RT}$$

What is the Combined gas law equation?

$$\frac{P_1 V_1}{T_1} = \frac{P_2 V_2}{T_2}$$

What is the Avogadro's law equation?

$$\frac{n_1}{V_1} = \frac{n_2}{V_2}$$

What does Avogadro's law state?

At constant $P$ and $T$, volume is directly proportional to moles.

What is the Boyle's law equation?

$$P_1 V_1 = P_2 V_2$$

What does Boyle's law state?

At constant $T$ and $n$, pressure and volume are inversely related.

What is the Charles's law equation?

$$\frac{V_1}{T_1} = \frac{V_2}{T_2}$$

What does Charles's law state?

At constant $P$ and $n$, volume and temperature are directly related.

What is the Gay-Lussac's law equation?

$$\frac{P_1}{T_1} = \frac{P_2}{T_2}$$

What does Gay-Lussac's law state?

At constant $V$ and $n$, pressure and temperature are directly related.

What is Dalton's law equation for total pressure?

$$P_T = P_A + P_B + P_C + \dots$$

What is Dalton's law equation using mole fraction?

$$P_A = X_A \times P_T$$

What does Dalton's law state?

Total pressure equals the sum of all component partial pressures.

What is the Henry's law equation?

$$[A] = k_H \times P_A$$

What does Henry's law state?

Dissolved gas concentration is directly proportional to its partial pressure.

What is the equation for the average kinetic energy of a gas?

$$KE = \frac{1}{2}mv^2 = \frac{3}{2} k_B T$$

What is the root-mean-square speed equation?

$$v_{\text{rms}} = \sqrt{\frac{3RT}{M}}$$

What is the Graham's law equation?

$$\frac{r_1}{r_2} = \sqrt{\frac{M_2}{M_1}}$$

What does Graham's law state?

Lower-molar-mass gases diffuse and effuse faster.

What is diffusion?

Particles spread from high to low concentration.

What is effusion?

Gas passes through a small opening under pressure.

What are STP temperature and pressure?

$273\,K$ ($0\,^\circ C$) and $1\,atm$

What volume does 1 mole of ideal gas occupy at STP?

$$22.4\,L$$

How does average kinetic energy relate to temperature?

Average kinetic energy is directly proportional to absolute temperature.

What volume do ideal gas particles have?

Negligible particle volume.

Do ideal gas particles have intermolecular forces?

No; attractions and repulsions are assumed negligible.

What type of collisions occur between ideal gas particles?

Elastic collisions.

When do real gases deviate most from ideal behavior?

High pressure and low temperature.

Why can intermolecular attractions reduce real-gas volume?

Attractions pull gas particles closer together.

What does van der Waals constant $a$ correct for?

Intermolecular attractions.

What does van der Waals constant $b$ correct for?

Finite molecular volume.