The effective atomic number (EAN) of Ni in [Ni(CO)4] is: (Ni atomic number = 28)
EAN = 28 − 0 + 2 × 4 = 36.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Geometrical Isomerism in Coordination Compounds
#atomic number
14 public questions tagged with this topic.
Filter questions
What is the magnetic moment (in BM) of Fe 3+ ion? (Atomic number of Fe = 26)
Fe 3+ has 5 unpaired electrons (3d 5 ). Magnetic moment = √[5(5+2)] = 5.92 BM.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Oxidation States and Colour and Magnetic Properties of d-Block
What is the temporary systematic name of the element with atomic number 115?
For Z=115: 1 (un), 1 (un), 5 (pent) → ununpentium (before being named Moscovium).
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Nomenclature of Elements with Atomic Number >100
What is the IUPAC name of the element with atomic number 113?
Elements with Z > 100 have systematic IUPAC names until officially named. For 113: 1 (un), 1 (un), 3 (tri) → ununtrium. However, it’s now officially Nihonium (Nh).
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Nomenclature of Elements with Atomic Number >100
What is the temporary systematic name of the element with atomic number 113?
For Z=113: 1 (un), 1 (un), 3 (tri) → ununtrium (before being named Nihonium).
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Genesis of Periodic Classification - Dobereiner Newlands Mendeleev
Which of the following has the same number of electrons as Ar (atomic number 18)?
K⁺ has 18 electrons.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Quantum Numbers - Principal Azimuthal Magnetic Spin
The electronic configuration of an element is 1s² 2s² 2p⁶ 3s² 3p³. What is the atomic number of this element?
Total electrons = 15. Atomic number = 15.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Electronic Configuration - Aufbau Pauli Hund and Stability
An atom has an electronic configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s¹. What is its atomic number?
Total electrons = 2+2+6+2+6+10+1 = 29.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Electronic Configuration - Aufbau Pauli Hund and Stability
An atom has the electronic configuration 1s² 2s² 2p⁶ 3s² 3p⁵. What is its atomic number?
Total electrons = 2+2+6+2+5 = 17.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Electronic Configuration - Aufbau Pauli Hund and Stability
An atom has an electronic configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 3d². What is its atomic number?
Total electrons = 2+2+6+2+6+2 = 20. Atomic number = 20.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Electronic Configuration - Aufbau Pauli Hund and Stability
How many protons, neutrons, and electrons are present in the neutral atom with atomic number 35 and mass number 80?
Protons = electrons = atomic number = 35. Neutrons = mass number - atomic number = 80 - 35 = 45.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Discovery of Subatomic Particles - Electron Proton Neutron
How many neutrons are present in an atom with atomic number 19 and mass number 39?
Neutrons = mass number - atomic number = 39 - 19 = 20.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Atomic Models - Thomson Rutherford and Bohr Model