The number of spectral lines that are possible when electrons in 7th shell in different hydrogen atoms return to the 2nd shell is: A.12 B.15 C.14 D.10
Answer: B.15 Number of spectral line = [(n2 – n1) (n2 – n1 + 1)]/2 = [(7−2) (7−2+1)]/2 = 15
Latest Posts
Which of the following contains the largest number of atoms? (A) 11g of CO2 (B) 4g of H2 (C) 5g of NH3 (D) 8g of SO2
Answer: (B) 4g of H2 Explanation: (A) 11g of CO2 1 mole of CO2 = 3 NA atoms 44 g... View Article
What do you mean by a concentration of a solution ? Mention two ways, of expressing the concentration of a solution.
Concentration of the solution is the amount of solute present in one liter of solution. The two ways of expressing... View Article
Resonating structure of SO3:
Resonance structures are sets of Lewis structures that describe the delocalization of electrons in a polyatomic ion or a molecule.... View Article
From which mineral silicon is obtained?
Silicon is the second (27.7 % by mass) most abundant element on the earth’s crust and is present in nature... View Article
Which one of the following is an extensive property? a. Volume b. Surface tension c. Viscosity d. Density
Answer: (a) Volume Volume depends upon the mass of the substance, hence it’s an extensive property.
In ZnO + C = Zn + CO, which substance is oxidized and reduced?
In ZnO + C —> Zn + CO, Carbon is oxidized (due to loss of electrons) and Zinc is reduced... View Article
Which one of the following is aromatic? (a) Cyclopentadienyl cation (b) Cyclooctatetraene (c) Cycloheptatriene (d) Cycloheptatrienyl cation
Answer: (d) Cycloheptatrienyl cation Aromatic compounds are chemical compounds that consist of conjugated planar ring systems accompanied by delocalized pi-electron clouds in place of individual alternating double... View Article
The lanthanide contraction is responsible for the fact that (a) Zr and Y have about the same radius (b) Zr and Nb have similar oxidation state (c) Zr and Hf have about the same radius (d) Zr and Zn have the same oxidation state
The lanthanide contraction is responsible for the fact that Zr and Hf have about the same radius. Therefore, the correct... View Article
The main constituent of natural gas is: (a) Methane (b) Ethane (c) Propane (d) Butane
Natural gas is primarily composed of methane. Hence, the main constituent of natural gas is methane. So, the correct answer... View Article
The most acidic compound among the following is: (a) phenol (b) ethanol (c) 3,5-dinitrophenol (d) 4,4-methoxyphenol
The correct answer is option (c) i.e 3, 5-dinitrophenol. Nitro is a — R group i.e strong electron withdrawing group.... View Article
When Na2CO3 is heated it gives: (a) Na2O (b) CO2 (c) Both (a) and (b) (d) NO2
Na2CO3 is the chemical formula of sodium bicarbonate. It undergoes a thermal decomposition reaction on heating. The reaction of decomposition... View Article
Explain filtration with help of examples and diagram.
Filtration is technically defined as the process of separating suspended solid matter from a liquid, by causing the latter to... View Article
Draw the electron dot structure of H2.
The electron dot structure or Lewis structure of H2 (H-H) is given below:
The correct order of a dipole moment is: A. CH4 < NF3 < NH3 < H2OB. NH3 < NF3 < CH4 < H2OC. NF < CH4 < NH3 < H2OD. H2O < NH3 < NF3 < CH4
Answer: A. CH4 < NF3 < NH3 < H2O Solution A dipole moment arises in any system in which there... View Article
The chemical formula of magnesium sulphate is:
The chemical formula of magnesium sulphate is MgSO4. Also see: Magnesium Sulphate Formula
Ammonia and hydrogen chloride gases are mixed. Which type of chemical reactions it gives?
Ammonia = NH3 Hydrogen Chloride = HCl NH3 + HCl —> NH4Cl Thus the resulting compound is Ammonium chloride
Identify conductor and insulator from following :- Sulphur , Silver , Copper , Cotton , Aluminium , Air , Nichrome , Graphite , Paper , Porcelain , Mercury, Mica , Bakelite , Polythene , Manganin.
Conductors are: Silver , Copper , Aluminium , Nichrome , Graphite , Mercury , Manganin. Insulators are: Sulphur , Cotton... View Article
The order of stability of the following carbocations:
The order of stability of the given carbocation is: III > I > II
Assign the oxidation number to MN in K2 MnO4.
Let us say oxidation state of Mn is x. Now, we know, the oxidation state of Oxygen is -2 and... View Article
