Concept explainers
The chromium in an aqueous sample was determined by pipetting 10.0 ml. of the unknown into each of five 50.0-mL volumetric flasks. Various volumes of a standard containing 12.2 ppm Cr were added to the flasks,
following which the solutions were diluted to volume.
Unknown,mL Standard, mL Absorbancc
10.0 0.0 0.201
10.0 10.0 0.292
10.0 20.0 0.378
10.0 30.0 0.467
10.0 40.0 0.554
(a) Plot the data using a spreadsheet.
(b) Determine an equation for the relationship between absorbance and volume of standard.
(c) Calculate the statistics for the least-squares relationship in (b).
(d) I)ctcrmine the conccnt ration oÍCr in ppm in the sample.
(e) Find the standard deviation of the result in (d).
Trending nowThis is a popular solution!
Chapter 9 Solutions
PRINCIPLES OF INSTRUMENTAL ANALYSIS
- In intercalation compounds, their sheets can be neutral or have a negative or positive charge, depending on the nature of the incorporated species and its structure. Is this statement correct?arrow_forwardThis thermodynamic cycle describes the formation of an ionic compound MX2 from a metal element M and nonmetal element X in their standard states. What is the lattice enthalpy of MX2 ? What is the enthalpy formation of MX2 ? Suppose both the heat of sublimation of M and the ionization enthalpy of M were smaller. Would MX2 be more stable? Or less? or impossible to tell without more information?arrow_forward7. Draw the mechanism to describe the following transformation: Note: This is a base catalyzed reaction. So, the last steps must make [OH]- OH [OH]¯ OH Heat Oarrow_forward