Atomic structure and chemical bonding Flashcards
Protons and neutrons collectively known as
NUCLEONS
Name three subatomic particles
Protons, Neutrons and Electrons
Positively charged subatomic particle
Proton
Negatively charged subatomic particle
Electron
Neutral subatomic particle
Neutron
Mass of Proton (also mass of neutron)
1 amu
Atom is electrically neutral. Give reason
Protons are equal in number and opposite in charge(+1) with electrons(-1) and neutrons have no charge
Define atomic number
The number of protons present in the nucleus of an atom
The atomic number of X^-2 ion where total number of
electrons=18 is
16
Define Mass number
The sum of number of protons and neutrons in an atom
The shell closest to the nucleus
K shell
Which electron has minimum energy? The one preseng in L shell or the one present in N shell?
The electron present in L shell
While revolving in a shell an electron possesses a certain amount of energy. Hence shells are also called
Energy levels
Define electron configuration
distribution of elctrons in different shells
The two scientists who gave scheme to distribute electrons in different orbits
Bohr and Bury
Maximum number of eletrons which can be present in any shell is given by
2n^2
The outermost shell can not have more than __ electrons
8
The penultimate shell cannot have more than ___ electrons
18
Electron configuration of Calcium ion (at no. 20)
2,8,8
Define isotopes
Atoms of the same element having same atomic number but different mass number
Noble gases do not gain, lose or share elctrons. Why?
They have stable elctronic configuration ie their outermost shell is complete
Name the 3 isotopes of Hydrogen
Protium, Deuterium, Tritium
Chlorine has 2 isotopes, Cl-35 and Cl-37. But its average atomic mass is 35.5 and not 36. Why?
Because the Cl-35:Cl-37 existence ratio is 3:1. 1 atom of Cl-37 mass is 37 and 3 atoms of Cl-35 mass is 105. Hence avg mass is 142/2=35.5
What is DUPLET arrangement of elctrons?
2 electrons in outermost shell ie K shell
What is OCTET arrangement of electrons
8 electrons in the outerost shell of an atom
Which type of chemical bond is formed by transfer of electrons from one atom to another?
Ionic bond / Electrovalent bond
Which type of chemical bond is formed by mutual sharing of electrons between 2 atoms?
Covalent bond
Chemical properties of iostopes of same element are similar. Why?
Chemical properties are dependent on the electronic configuration of an atom. Isotopes have same atomic number, same number of electrons and hence same electron configuration
Physical properties of isotopes of the same element are different. Why?
Physical properties are dependent on the atomic mass. Isotopes have different mass number, different number of neutrons and hence different atomic masses
The driving force for the atoms of elements otherthan Noble gases to combine chemically with other elements is
To attain stable electronic configuration of the nearest Noble gas
Calcium will attain stable electronic configuration by ____ ____ ____ electrons
loss of two
Chlorine will attain stable electronic configuration by ____ ____ ____ electrons
gain of one
Name the type of bond present in following compound.
CaO
Ionic / Electrovalent bond
Name the type of bond present in following compound.
HCl
Covalent bond
Name the type of bond present in following molecule.
Hydrogen
Covalent bond
Name the ions responsible for the formation of Magnesium chloride, also mention total number of ions required.
Mg^+2 and 2 Cl^-1
What is a lone pair of electrons
A pair of valence electrons that are not shared with another atom in a covalent bond and is sometimes called an unshared pair or non-bonding pair.
The eletron configuration of Nitrogen is 2,5. How many electrons in the outermost shell of a nitrogen atom are not involved in the formation of Nitrogen molecule.
1 pair
The eletron configuration of Nitrogen is 2,5. How many electrons in the outermost shell of a nitrogen atom are not involved in the formation of Nitrogen molecule.
1 pair
A molecule containing double covalent bond is
O2
What is the number of covalent bonds present in each of the following molecules.
1) NaCl 2) CaO 3) MgCl2
None
A molecule which is having single covalent bond(s) in given list.
Hydrogen, Nitrogen, Ammonia, Oxygen, water, methane, carbon tetrachloride
Hydrogen, Ammonia, water, methane, carbon tetrachloride
How many pairs of electrons are shared between H and Cl atom in the formation of HCl molecule
1 pair of electrons
The number of lone pair of electrons present in following molecules.
1) H2 2) O2 3) H2O 4) NH3 5) N2 6) CH4 7) CCl4 8) Cl2
1) 0 2) 4(2 on each O) 3) 2 4) 1 5) 2(each on 1 N) 6) 0
7) 12 (3 on each Cl) 8) 6 ( 3 on each)
Atomic number of following elements given below:
A=8, B=7, C=17, D=11, E=20
1) Which of the above is divalent metal?
E
Atomic number of following elements given below:
A=8, B=7, C=17, D=11, E=20
1) Which of the above is non-metal?
A, B, C
Atomic number of following elements given below:
A=8, B=7, C=17, D=11, E=20
1)The type of bonding between two atoms of A
double covalent bond
Atomic number of following elements given below:
A=8, B=7, C=17, D=11, E=20
1) The type of bonding between D and C.
Ionic bond
Atomic number of following elements given below:
A=8, B=7, C=17, D=11, E=20
1) Number of covalent bonds formed in a molecule of B2
One triple covalent bond
A covalent molecule, having two lone pair of electrons
water
A covalent molecule, having triple covalent bond
Nitrogen molecule
A covalent hydrocarbon molecule, having four single covalent bonds
methane
