Structure of Atom
Which of the following scientist discovered the neutron?
R. A Millikan
How many protons does the below element contain?
If 100 atoms of element X contains 70 atmos of 9X and 30 atoms of 11X, Calculate the relative atomic mass of X
How many orbitals are associated with th p-sub energy level?
Which of the following elements has the electronic configuration: 1s22s22p63s23p1? [11Na, 13Al, 14N, 16S ]
Which of the following ions is isoelectronic with neon? [3Li, 9F, 10Ne, 17Cl, 19K]
Which of the following statements about the behaviour of the atom is correct?
Atomic size decreases down the group
Atomic size increases along the period
Anions are smaller than the parent atom
Cations are smaller than the parent atom
The mass spectrometer can be used to measure mass of
Find the number of neutrons in an atom represented by
The valence electrons in a chloride ions are [17cl]
2p electrons only
3s and 3p electrons only
3p and 3d electrons only
3p electrons only
What is the atomic number of an element whose cation Y+ has the electronic configuration 1s22s22p6?
Atom below decay by alpha emission to give an atom R. The atomic number and mass number of atom R are respectively
86 and 230
87 and 234
88 and 233
90 and 238
Consider the following elements and their electronic configuration: W: 1s22s2, X:1s22s22p6 , Y:1s22s22p63s2 Z:1s22s22p63s23p2
Which of the element belong to the same group in the Periodic table?
W and X only
Y and Z only
W and Y only
W, Y and Z only
When sodium atom forms the ion Na+,
It gains one electron
It gains one proton
It achieves a noble gas configuration
Its diatomic number increases
Which of the following statements about rare gases are correct?
I Their outermost shells are fully filled
II They are generally unreactive
III Their outermost shells are partially filled
IV They have lone pair of electrons in their outermost shell
I and II only
II and III only
I, II and III only
I, II, III and IV
How many electron are in then ions F-? [F]
What is the value of X in the following nuclear reaction? B+ → CfLr + 3n
In which of the following atoms is the ionic radius larger than the atomic radius? [11Na, 12Mg, 13Al, 17Cl]
An atom as shown below decays by alpha particle emissions to give an atom Y.
238 X 93
90 and 234 respectively
91 and 238 respectively
92 and 236 respectively
93 and 238 respectively
An element with mass number 133 and atomic number 55 has
55 electrons and 55 neutrons
55 electrons and 78 neutrons
78 electrons and 78 neutrons
78 electrons and 55 neutrons
Which of the following pairs of species contains the same number of electron? [6C, 8C, 10Ne, 11Na, 12Mg, 13Al, 17Cl]
Mg2+ and Al3+
Cl- and Ne
Na+ and Mg
C and O2-
An element X has electronic configuration 1s2 2s2 2p6 3s2 3p6 4s. To which group in the periodic table does X belong?
Which of the following sets of element is arranged in order increasing first ionization energies?
11Na, 3Li, 19K, 37Rb
37Rb, 19K, 3Li, 11Na
3Li, 19K, 11Na, 37Rb
37Rb, 19K, 11Na, 3LI
The electronic configuration of an element X is 1s22s22p63s23p4. It can be deduced that X
belongs to group 6 of the periodic table
belongs to period IV of the periodic table
has 3 unpaired electrons in its atom
has relative molecular mass of 16
What is the mass number of an element having 20 neutrons, 15 protons and 15 electrons?
Consider the table below:
J and K
K and L
J and L
K and M
An element which can exist in two or more forms in the physical state, exhibits
The mass of an element is 27 and its atomic number is 13. What is the composition of the nucleus of its atom?
13 electrons and 14 protons
13 neutrons and 14 protons
13 protons and 14 neutrons
13 electrons and 14 neutrons
If an atom is represented as shown below, which of the following deductions are correct?
It contains 20 protons
It forms a covalent chloride
Its atomic number is 39
Its an alkali metal
Two elements X and Y combine to form a compound formular X2Y3. Which of the following representation would fi the configuration of X and Y?
Which of the following electrons transitions results in the emission of energy?
3p to 3s
3p to 4p
2s to 2p
1s to 2s
Which of the following equipment is not used to do radioactivity?
Wilson cloud chamber
The electronic configuration of an element is 1s22s22p63s23p3 . Where is the element located in the periodic table?
Group III, period 3
Group III, period 5
Group V, period 3
Group V, period 5
The electrons that are most easily removed from the below element are in which orbital?
If the relative molecular mass of an element is not a whole number, it can be deduced that the element is
abundant in nature
a transition metal
an isotopic mixture
The atom of an element X is represented by as X. The basic properties of X depend on the value of
y - Z
Z - Y
The conclusion from Rutherford's Alpha scattering experiment is that
atoms are mostly empty space with a small nucleus
emissions from radioactive substances consist of three main components
there is a nuclear pull on the orbital electrons
electrons are deflected by both magnetic and electric fields
Which of the letters indicate elements which exist as diatomic gases?
W and Z
M and J
M and Y
Y and Q
Which of the following pairs of letters denotes elements containing the same number of electrons in their outermost shells?
J and X
M and Q
W and Z
W and Y
Given that the electronic configuration of an element X is 1s22s22p63s23p4, it can be deduced that X
belongs to group VI in the Periodic Table
belongs to period 4 in the periodic table
contains 3 unpaired electrons in the ground state
has atomic number 27
A sheet of paper is placed in the path of a beam from a radioactive source. The emissions that pass through the paper consist of
alpha particles and gamma rays
alpha and beta particles
beta particles and gamma rays
alpha particles only
Which of the following features of a human skeleton can be determined by carbon-dating?
The atoms of four elements are represented as 20Q 16R 10S and 8T. Which of the elements would be unreactive?
Chlorine atoms forms Cl- by
losing one electron
sharing one electron
donating one pair of electron
gaining one electron
An element Z has a combining power of 3. Which of the following formulae is correct of its compound?
A radioactive solid is best stored
under paraffin oil
under ultraviolet light
in cool, dark cupboard
in a box lined with lead
Which of the following atoms contains the highest number of electrons in the outermost shell?
Pauli Exclusion Principle is related to
quantum numbers of electron
reversibility of equilibrium reactions
electronegativity values of elements
collision theory of reaction rates
Which of the orbitals 4s, 4p, 4d and 4p has the lowest energy?
Which of the following has neither mass nor charge?