Define mass spectrum.
ANSWER: Mass Spectrum: “Mass spectrum is a plot of data in such a way that m/e is plotted as abscissa (x-axis) and the relative number of ions as ordinate (y-axis).” The number of peaks represents the number of isotopes while…
Category Objective Chemistry-11 Soft Book
Define mass spectrometer and mass spectrometry.
ANSWER: Mass Spectrometer & Mass Spectrometry: “The instrument used to measure the exact masses of the isotopes of an element is called mass spectrometer and the technique is called mass spectrometry.” (Ref. An Insight Into Objective Chemsitry-11, Ch-01, Q. No.…
What are mono-isotopic elements?
ANSWER: Mono-Isotopic Elements: “The elements having only a single isotope are called mono-isotopic elements.” Examples: Gold, Iodine, arsenic, Fluorine, etc. (Ref. An Insight Into Objective Chemsitry-11, Ch-01, Q. No. 18)
Why do isotopes have same chemical but different physical properties?
ANSWER: Chemical properties depend upon atomic number, i.e., the number of protons or the number of electrons and their arrangement in valence shells. Since, isotopes have same atomic number, they have same chemical properties. Physical properties depend upon atomic masses…
What is amu?
ANSWER: Atomic Mass Unit (amu): “The unit used to express the relative atomic mass is called atomic mass unit (amu). It is 1/12th of the mass of one carbon atom.” On C–12 scale, the relative atomic mass of 6C12 is…
What is relative atomic mass?
ANSWER: Relative Atomic Mass: “Relative atomic mass is the mass of an atom of an element as compared to the mass of an atom of carbon taken as 12.” We use the term relative atomic mass because the given masses…
Differentiate between ion and molecular ion.
ANSWER: ION MOLECULAR ION 1) “Those species which carry either positive or negative charge are called ions.” 2) Anions having group of atoms are more abundant than cations.3) Examples: K+, Mg2+, Al3+, O2–, CO32– etc. 1) “When a molecule loses…
Define molecular ions with examples.
ANSWER: MOLECULAR IONS: “When a molecule loses or gains an electron, it forms a molecular ion.” Formation of Molecular Ions: Molecular ions can be generated by passing high-energy electron beams or α-particles or X–rays through a substance present in gaseous…
The formation of a uninegative ion is an exothermic reaction. Explain.
ANSWER: The formation of a uninegative ion is an exothermic reaction. This is because energy is released when an extra electron enters a neutral atom and is attracted by its nucleus. B + e– ⟶ B– ∆H = Negative (Ref.…
The formation of a positive ion is an endothermic reaction. Explain.
ANSWER: The formation of a positive ion is always an endothermic reaction. The reason is that positive ion is formed by the removal of one or more electrons from the neutral atom. Since, electrons are strongly held by the nucleus,…