Chemistry Instrumentation SOLO 2 Kahoot

Absorbance is calculated from transmittance by which formula? (L1S8)

A = 2-log %T

Which statement best describes Beer’s Law? (L1S9)

Absorbance is directly proportional to the concentration

A fluorescing molecule absorbs light then emits light of (L2S6)

A longer wavelength (lower energy)

Which statement about atomic absorption (AA) spectrophotometry is correct? (L2S3)

Measures absorbance of light by atoms, not molecules

Which statement about nephelometry is correct? (L2S19)

Measures scattered light blocked at 180 degrees from incident light

Milky, lipemic serum run on a nephelometric estrogen assay: likely outcome? (L2S23)

Lipemia causes background light scatter/interference

Testing 50%T on either side of peak transmittance assesses a filter’s

Bandpass (spectral bandwitdth)

125 mg/dL glucose std, Abs 0.20. Patient ABs 0.24 Conc = ? (L1S25)

150 mg/dL

Protein calibrator 6 g/dL, Abs 0.5. Patient Abs 0.6. Conc = ? (L1S25)

7.2 g/dL

Which wavelength falls within the near-ultraviolet region? (L1S5)

220 nm

Diluted 1:10, very high FT4 fluorometric result reads “<0.05” Why? (L2S23)

Dilution wasn’t enough, hook effect suppressed signal

Fluorescent technique using rotation of small vs large labeled molecules? (L2S11)

Fluorescence polarization immunoassay (FPIA)

Which component isolates a specific wavelength, excluding others? (L1S17)

Monochromator

AAS is frequently used in clinical labs to measure (L2S14)

Elements and trace metals

The light source in an atomic absorption spectrophotometer is typically a (L2S3)

Hollow-cathode lamp

Which technique is more sensitive at low analyte concentration, and why? (L2S12)

Fluorescence; measured against a dark (zero) background

Which optical technique is NOT considered an emission technique? (L2S3-5)

Atomic absorption spectrophotometry

Difference between max excitation and max emission wavelength is called (L2S8)

Stokes shift

Wavelengths of the electromagnetic spectrum are traditionally measured in (L1S4)

Nanometers (nm)

True or false: The visible spectrum spans about 380-750nm (L1S5)

True

Which electrochemical technique routinely measures serum/plasma chloride?

Ion-selective electrode (potentiometry)

Measuring the voltage difference between two half-cells is called (L3S17)

Potentiometry

A voltage potential from chemical equilibrium of electron transfer is (L3S18)

Redox potential

A common glass reference electrode for pH measurement is the ____ electrode (L3S25)

Calomel

Which statement correctly describes a PCO2 electrode? (L3S29)

CO2 diffuses through a membrane, forming carbonic acid

Which neutral antibiotic in a PVC membrane makes a K+ selective electrode? (L3S28)

Valinomycin

That type of K+ ISE belongs to which category of electrodes? (L3S24)

Polymer membrane electrodes

Potentiometric measurements (galvanic cells) consist of (L3S16)

Two conducting electrodes joined by electrolyte

Voltammetry and amperometry are based on which cell type? (L3S8)

Electrolytic cell

The predominant potentiometric electrode in clinical labs is the (L3S24)

Polymer membrane ISE

Most immunoassays use which immunoglobulin for antigen specificity?

IgG

Two examples of luminescent labels used in chemiluminescence are (L2S17)

Luminol and acridinium esters

If a signal reads below the analytic measurement range, you should

Repeat testing and report <AMR

Which statement best contrasts galvanic and electrolytic cells? (L3S6)

Galvanic is spontaneous; electrolytic needs voltage

A substance that loses/donates electrons is called a (L3S9-11)

Reductant

Max potential difference between electrodes at zero current defines (L3S19)

Electromotive force (EMF)

The formula for calculating absorbance of a solution is (L1S13)

Absorptivity x light path x concentration

Correct light pathway through a single-beam spectrophotometer? (L1S14-15)

Source → monochromator → sample → detector → readout

What is the purpose of a monochromator? (L1S21)

Isolate a single wavelength/band of light

Stray light in a spectrophotometer limits accurate measurement of (L1S27)

Absorbance at the upper end of linearity

175 mg/dL glucose std, Abs 0.655. Patient Abs 0.445. Conc = (l1S28)

119 mg/dL

Which component is found only in a fluorometer, not a spectrophotometer? (L2S15)

An excitation source

Current-based technique; gold standard for chloride in serum/plasma (L3S30)

Coulometry