Tag: measurement and data processing and analysis

Questions Related to measurement and data processing and analysis

Borax bead test is given by:

  1. $Na{NO} _{3}$

  2. $Fe{SO} _{4}$

  3. $Cu{SO} _{4}$

  4. ${NH} _{4}Cl$


Correct Option: C
Explanation:

Borax bead test is given by $CuSO _{4}$, hence, option C is correct.

Which of the following fact(s) explain(s) as to why p-
nitrophenol is more acidic than phenol?
I. - I Effect of nitro group.
II. Greater resonance effect of $p$ -nitrophenoxy group
II. Steric effect of bulky nitro group

  1. I and II

  2. I and III

  3. II and III

  4. II alone


Correct Option: A
Explanation:
P nitrophenol is stronger acid than phenol
The nitro-group is an electron-withdrawing group. The presence of this group in the ortho or para position decreases the electron density in the OH bond. As a result, it is easier to lose a proton. ... Hence, ortho and para nitrophenols are stronger acids than phenol.

Equimolar mixture of a $\alpha-D(+)$- glucose and $\beta-D(+)$-glucose has specific rotation (${[\alpha]} _{D}$) is:

  1. $-{92.4}^{o}$

  2. $+{112.5}^{o}$

  3. $+{52.5}^{o}$

  4. $-{19.2}^{o}$


Correct Option: C
Explanation:
The specific rotation of α-D-glucopyranose decreases from +112° to +52.5°.
The specific rotation of β-D-glucopyranose increases from +19° to +52.5°.
The specific rotation of equimolar mixture of  $\alpha$ - D(+) - glucose and $\beta$ - D(+) - glucose has a specific rotation $52.5^0$.

Hence, the correct option is C.

When does a precipitate form?

  1. When something is insoluble in solution.

  2. When something is soluble in solution.

  3. When too much of a substance is added to solution.

  4. Whenever a solid is added to solution.

  5. Whenever liquid is added to a solution.


Correct Option: C
Explanation:

When too much of a substance is added to solution, a precipitate forms.
Also, when ionic product exceeds solubility product, the precipitation occurs.
In a supersaturated solution, the excess ions recombine to form solid which results in precipitation.

What is a macromolecule?

  1. A huge molecule made up of smaller sub units called monomers

  2. A huge molecule made up of smaller sub units called polymers

  3. A huge molecule found only in living things

  4. A huge molecule that contains carbon

  5. A molecule made of larger subpieces


Correct Option: B
Explanation:

A macromolecule is a term used to contrast a micromolecule (which is smaller in size and in molecular weight). Macromolecules are usually used to refer to large biological polymers, such as nucleic acids and proteins, which are made up of small monomers linked together.

Which of the following method is the fastest and most cost-efficient method for determining the order of the reaction involved in the laboratory?

  1. Mass spectrometry

  2. Spectrophotometry

  3. Titration

  4. Paper chromatography


Correct Option: A
Explanation:

Mass spectrometry (MS) is an analytical technique that measures the mass-to-charge ratio of ions. The results are typically presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio.It helps in calculating order of reaction.

Which of the following anions neutralize the acidic pH of the chime that enters into the duodenum from the stomach?

  1. $H _2PO^- _4$

  2. $HSO^- _4$

  3. $HCO^- _3$

  4. $CH _3COO^-$


Correct Option: C
Explanation:

$HCO _3$ which is produced by the duct cells helps in neutralizing the acidic chime. It creates an optimum pH for the digestive enzymes in the duodenum.

Which organic macromolecule is responsible for genetic information?

  1. Nucleic Acid

  2. Protein

  3. Nucleus

  4. Lipid

  5. Carbohydrate


Correct Option: A
Explanation:

Nucleic acid are the organic molecules responsible for genetic information.
Organic Macro-molecules: Organic compounds are those that contain carbon (e.g. carbohydrates, lipids, proteins, nucleic acids).

Given the numbers $786$, $0.786$ and $0.0786$. The number significant figures for the numbers is :

  1. $3$, $4$ and $5$ respectively

  2. $3$, $3$ and $3$ respectively

  3. $3$, $3$ and $4$ respectively

  4. $3$, $4$ and $4$ respectively


Correct Option: B