An ion with mass number 37 possesses one unit of negative charge. If the ion contains '11.1 %' more neutrons than the electrons, find the symbol of the ion.

An ion with mass number 56 contains 3 units of positive charge and '30.4 %' more neutrons than electrons. Assign the symbol to this ion.

An element with mass number 81 contains '31.7 %' more neutrons as compared to protons. Assign the atomic symbol.

Assertion : Alcohols and water are weaker acids than phenols. Reason : The delocalisation of negative charge makes the phenoxide ion more stable and favour the ionisation of phenol.

The element Cu with atomic number 29 undergoes chemical reaction to form an ion with oxidation number +2. a) Write down the subshell electronic configuration of this ion? b) Can this element show variable valency? Why? c) Write down the chemical formula of one compound formed when this elemrnt reacts with chlorine (Cl_17)

For one-electron species, the wave number of radiation emitted during the transition of electron from a higher energy state (n_(2)) to a lower energy state (n_(1)) is given by: bar v =(1)/(lamda)=R_(H) xx Z^() ((1)/(n_(1)^(2)) (1)/(n_(2)^(2))) where R_(H)=(2 pi m_(s) k^(2) c^(4))/(h^(3) c) is Rydberg constant for hydrogen atom. Now, considering nuclear motion, the accurate measurement would be obtained by replacing mass of electron (m_(e)) by the reduced mass (mu) in the above expression, defined as mu =(m_(n)xx m_(e))/(m_(n) +m_(e)) where m_(n) = mass of nucleus. For Lyman series, n_(t) =1 (fixed for all the lines) while n_(2) = 2, 3, 4 .... For Balmer series: n_(1) = 2 (fixed for all the lines) while n_(2) = 3,4,5 .... If proton in hydrogen nucleus is replaced by a positron having the same mass as that of an electron but same charge as that of proton, then considering the nuclear motion, the wavenumber of the lowest energy transition of He+ ion in Lyman series will be equal to