Answer:
The experimental feature of the MALDI-MS technique which allows the separation of ions formed after the adduction of tissue molecules:
B) Velocity of ions depends on the ion mass-to-charge ratio.
Explanation:
- The option a is not correct as distance traveled by ions doesn't depend upon the ion charge rather it depends upon time for which you leave the sample to run.
- The option b is correct as velocity of ions depends on the ion mass-to-charge ratio because separation is done due to mass to charge ratio feature.
- The option c is incorrect as time of travel is not inversely proportional to the ion-to-mass ratio because the ion will move across the gel until you stop the electric field.
- The option d is not correct as electric field between MALDI plate and MS analyzer is though uniform but this feature doesn't allow the separation of ions.
Answer:
6.22 × 10⁻⁵
Explanation:
Step 1: Write the dissociation reaction
HC₆H₅COO ⇄ C₆H₅COO⁻ + H⁺
Step 2: Calculate the concentration of H⁺
The pH of the solution is 2.78.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -2.78 = 1.66 × 10⁻³ M
Step 3: Calculate the molar concentration of the benzoic acid
We will use the following expression.
Ca = mass HC₆H₅COO/molar mass HC₆H₅COO × liters of solution
Ca = 0.541 g/(122.12 g/mol) × 0.100 L = 0.0443 M
Step 4: Calculate the acid dissociation constant (Ka) for benzoic acid
We will use the following expression.
Ka = [H⁺]²/Ca
Ka = (1.66 × 10⁻³)²/0.0443 = 6.22 × 10⁻⁵
Hi , NaCl is basically salt , Na for sodium and Cl for chlorine , these elements make Sodium Chloride .The bond between them is ionic.
