Quiz 14 Flashcards
- If an analyte absorbs green, the color perceived is
red
blue
orange
violet
red
Within that wheel the colour an object appears to be is the colour complementary to the one it most strongly absorbs. As such, plants look green because they absorb red light most efficiently and the green light is reflected.
- Which of the following is not the characteristic of a reference electrode?
It must have a known output potential
It must have a constant output potential
Its output potential is dependent on the concentration of the solution
It is employed in conjunction with the indicator or working electrode
Its output potential is dependent on the concentration of the solution
- Which of the following is the purpose of added membrane in the glass membrane of the glass electrode?
They act as tighteners
They act as filters
They act as conditioners
They act as collectors
They act as tighteners
- Which of the following is not a failure in pH meters?
Defective electrodes
Defective input circuitry
Defective electronic circuitry
Defective calibration
Defective calibration
- When UV light is absorbed by the fluor molecules the light emitted is in which of the following colours?
pink
red
green
blue
blue
- Nuclear Magnetic Resonance (NMR) spectroscopy is used to determine structure in which of the following materials?
Radioactive materials
Insoluble chemical compounds
liquids
gases
liquids
NMR Spectroscopy is abbreviated as Nuclear Magnetic Resonance spectroscopy. Nuclear magnetic resonance (NMR) spectroscopy is the study of molecules by recording the interaction of radiofrequency (Rf) electromagnetic radiations with the nuclei of molecules placed in a strong magnetic field. An information-rich and non-destructive analytical tool, nuclear magnetic resonance (NMR) spectroscopy uses the inherent magnetic properties of specific atomic nuclei to reveal the structure, identity, concentration, and behavior of molecules in solid or liquid samples.
- Inductively Coupled Plasma (ICP) Spectroscopy’s principle is similar to which of the following?
Flame emission spectroscopy
Fourier transforms spectroscopy
Atomic emission spectroscopy
Absorption spectroscopy
Atomic emission spectroscopy
ICP (Inductively Coupled Plasma) Spectroscopy is an analytical method used to detect and measure elements to analyze chemical samples. What is ICP spectroscopy used for? Inductively coupled plasma mass spectrometry (ICP-MS) is an analytical technique that can be used to measure elements at trace levels in biological fluids.
- Which of the following is most often used in the chromatograph in GC-MS or Gas Chromatography - Mass Spectrometry?- Mass
curvette
paper support
capillary tube
flask
capillary tube
The GC works on the principle that a mixture will separate into individual substances when heated. The heated gases are carried through a column with an inert gas (such as helium). As the separated substances emerge from the column opening, they flow into the MS. What is the principle of gas chromatography and mass spectrometry? Gas chromatography mass spectrometry basic principles | Agilent It works by heating a liquid sample until it converts into a vapor that can be carried by a gas like helium or hydrogen. The gas (called a carrier gas or mobile phase) transports the sample through a long, thin glass or metal tube (column) that is coated with a chemical (stationary phase).
- Powerful analytical instrument but suitable for volatile chemicals only.
HPLC - High -Performance Liquid Chromatography
IR - Infrared Spectroscopy
GC - Gas Chromatography
NMR - Nuclear Magnetic Resonance
GC - Gas Chromatography
- What optimizes the precision of a calibration curve determination?
calibration and linear regression
environment
linear regression
method
calibration and linear regression
- It states that if a stress is applied to a system at equilibrium, the system will shift, if possible, in such a way as to reduce the stress.
Law of mass action
Le Chatelier’s principle
Rate law
Pauli exclusion principle
Le Chatelier’s principle
- In the reaction Na + Cl2 NaCl, what is the oxidizing agent?
NaCl
Cl
Na
Cl2
Cl2
- Choose the correct statement about a family of elements in the periodic table.
The atoms of all elements in a family have the same number of shells of electrons.
All elements in a family have the same physical state.
All elements in a family have the same chemical reactivity.
The atoms of all elements in a family have the same number of valence electrons.
The atoms of all elements in a family have the same number of valence electrons.
- The number that expresses the oxidation state of an atom of an element or groups of atoms is called the
indicator
valence
displacement factor
electrolyte
valence
- An uneven sharing of electrons between two atoms indicate
bonding
coupling
electronegativity
polarity
polarity
- The energy required to knock-off electrons from a neutral atom.
activation energy
ionization potential
transition energy
atomic energy
ionization potential
- The temperature at which a substance starts to burn.
boiling point
kindling temperature
ignition point
combustion temperature
kindling temperature
- According to Bronsted - Lowry theory, an acid is a substance that can
accept an electron pair
accept a proton
donate an electron pair
donate a proton
donate a proton
- What law governs the rate of reaction of a substance?
conservation of mass
Arrhenius law
law of mass action
Avogadro’s law
law of mass action
- In which colligative property (ies) does the value decrease as more solute is added?
boiling point
freezing point
osmotic pressure
freezing point & vapor pressure
freezing point & vapor pressure
- In condensation polymerization, the most common molecule eliminated is
ammonia
carbon dioxide
methane
water
water
- A superconductor
has zero resistance below some temperature
conducts heat very effectively at room temperature
has high electrical resistance
is unlikely to be a ceramic material
has zero resistance below some temperature
- In which case are adhesive forces involved?
viscosity
surface tension
capillary action
thermal conductivity
capillary action
- Which of the following is the most disordered?
gas near the condensation temperature
solid near the melting point
liquid near the freezing point
solid at very low temperature
gas near the condensation temperature
- Which one of the following is not a characteristic of a liquid?
does not expand to fill the container
flows readily
is almost incompressible
diffusion within it occurs rapidly
diffusion within it occurs rapidly
