The energy of the second Bohr orbit of the hydrogen atom is -328 kJ mol-1; hence the energy of the fourth Bohr orbit would be:
- 41 kJ mol-1
-1224 kJ mol-1
-284 kJ mol-1
-82 kJ mol-1
The current passing through the battery in the given circuit, is:
Three identical heat conducting rods are connected in series as shown in the figure. The rods on the sides have thermal conductivity 2K while that in the middle has thermal conductivity K. The left end of the combination is maintained at temperature 3T and the right end at T. The rods are thermally insulated from outside. In steady state, temperature at the left junction is \(T_1\) and that at the right junction is \(T_2\). The ratio \(T_1 / T_2\) is
The atomic structure of an element refers to the constitution of its nucleus and the arrangement of the electrons around it. Primarily, the atomic structure of matter is made up of protons, electrons and neutrons.
Dalton proposed that every matter is composed of atoms that are indivisible and indestructible.
The following are the postulates of his theory:
Several atomic structures of an element can exist, which differ in the total number of nucleons.These variants of elements having a different nucleon number (also known as the mass number) are called isotopes of the element. Therefore, the isotopes of an element have the same number of protons but differ in the number of neutrons. For example, there exist three known naturally occurring isotopes of hydrogen, namely, protium, deuterium, and tritium.