Equations & Graphs

• What is the act or process of equating?

  Equating or being equated
• What is the first definition of an equation?

  The state of being equal
• What does a mathematical equation assert?

  It asserts the equality of two expressions
• How is a mathematical equation typically written?

  As a linear array with an equal sign
• What does a chemical equation represent?

  A chemical reaction with reactants and products
• What is the term for the adjective form of equation?

  Equational
• What is the adverb form of equation?

  Equationally
• What are some applications of equations in pharmacy?

  Used for conversions, density, and dilutions
• What are the key uses of equations in pharmacy?

  • Rearranging
  • Deriving units
  • Noting constants and variables
  • Simplifying complex equations
• How do you calculate density?

  Density = mass/volume
• How can you rearrange the density equation to find mass?

  Mass = density x volume
• How can you rearrange the density equation to find volume?

  Volume = mass/density
• What are the hints for dealing with equations?

  • D = Diffusion coefficient
  • R = Gas constant
  • T = Absolute temperature
  • h = Viscosity
  • r = Radius of the diffusing particle
  • N = Avogadro’s number
• What is the Stokes-Einstein equation for diffusion coefficient?

  D = $\frac{RT}{6 \pi h r N}$
• What are the SI units of the diffusion coefficient D?

  kg m² s^-2 mol^-1 K^-1
• How do you compare diffusion coefficients of two drugs?

  Using the ratio of their diffusion coefficients
• What is the Henderson-Hasselbalch equation?

  pH = pKa + log{[salt]/[acid]}
• How do you calculate the amount of sodium acetate needed for a buffer?

  Using the Henderson-Hasselbalch equation
• What is the pKa of acetic acid?

  4.76
• How do you find the concentration of salt needed for a buffer?

  By solving the equation for log[salt]
• What should you always check when working with equations?

  Always check the units
• What are the key points for plotting graphs?

  • Enable data point plotting
  • Ensure graph fits well
  • Label all axes with units
  • Draw a smooth line through points
• Why is it important to plot graphs?

  To visualize trends in data sets
• What is the UV max for ibuprofen?

  221 nm
• How do you estimate the concentration of ibuprofen in solution X?

  Using the calibration curve
• What are the methods for predictive graphing?

  • Interpolation
  • Extrapolation
• What is interpolation in graphing?

  Joining points with a smooth line
• What is extrapolation in graphing?

  Extending the trend beyond known data
• What type of equations give straight line graphs?

  Equations in the format y = mx + C
• What is the general form of a parabola equation?

  y = kx² + C
• What is the general form of a hyperbola equation?

  y = k/x + C
• What is log linearization?

  • Converts equations to linear form
  • Facilitates easier data manipulation
• What is the gradient in log linearization?

  It represents the power of x
• What is the intercept in log linearization?

  It represents the log of the constant
• What are the characteristics of straight line graphs?

  • Slope (m) indicates gradient
  • Intercept (C) indicates y-value at x=0
• What is the equation of a straight line?

  y = mx + C
• What is the significance of the slope in a straight line graph?

  It indicates the rate of change
• What does the intercept represent in a straight line graph?

  The value of y when x = 0
• What are the key points for obtaining straight line graphs?

  • Ensure data points are plotted
  • Draw the best-fit line
  • Calculate the gradient and intercept
• What is the purpose of plotting data sets?

  To determine the rate constant of degradation