Answer:
2.35.
Explanation:
∵ pH = - log[H⁺].
[H⁺] = 4.5 x 10⁻³ M.
∴ pH = - log(4.5 x 10⁻³ M) = 2.346 ≅ 2.35.
Which is the basis of thin-layer chromatography?
A.) An electron beam excites atoms within the drug, which give off a characteristic X-ray spectrum.
B.) The drug gets carried through a stationary phase by a mobile phase and the retention time identifies the drug.
C.) The drug fragments have specific molecular weights that bind to the antibodies.
D.) The unknown amount of drug in a sample competes with a known amount of fluorescently labeled drug for binding to an antibody to that drug.
Answer:
B.) The drug gets carried through a stationary phase by a mobile phase and the retention time identifies the drug.
Explanation:
Chromatography is used in purifying complex mixtures of organic compounds. It uses the adsorption tendencies of compounds to seperate and identify them.
Chromatography is made up of two phases in contact, the stationary phase or non-mobile phase and the mobile phase. The movement of the mobile phase over the stationary phase causes the separation of a mixture into its constituents.
The stationary phase is made up of silica-gel or alumina in a solvent (an adsorbent) and the mobile phase or carrier is the organic solvent which is the drug.
Thin-layer chromatography is based on the separation of compounds as they move at different rates through a stationary phase under the influence of a mobile phase, due to their interactions with the stationary material.
Explanation:The basis of thin-layer chromatography (TLC) is the separation of compounds based on their differing rates of movement through a stationary phase, typically a slurry of solid beads of silica or a solid surface of these compounds, under the influence of a mobile phase. The substances are first dissolved in the mobile phase, and as the mobile phase moves through the stationary phase, the components of the mixture interact with the stationary phase to various extents. These interactions can result in different retention times, which are the times that solutes remain in the chromatography system before eluting. As a result, components with different chemical properties can be separated and identified.
TLC is characterized by its use of a stationary phase and a mobile phase, and relies on the physical and chemical interactions between the solute and these phases for separation. Compounds with different affinities for the stationary and mobile phases travel at different speeds, resulting in their separation.
If I have 3.5 moles of C, and excess Fe2O3 , how many moles of Fe can I produce?
2Fe2O3 + C → Fe + 300,
7 moles Fe
1.17 moles Fe
1.75 moles Fe
3.5 moles Fe
Answer:
3.5 moles Fe
Explanation:
From the equation, Reaction of 2 moles of Fe₂O₃ with 1 mole of C produces 1 mole of Fe. When excess Fe₂O₃ is used, the only liming factor is C.
The ratio of amount of C used to the amount of Fe produced is 1:1
Therefore, if 3.5 moles of C are used, 3.5 moles of Fe are also produced.