An example of ionic compound is:
(d)
Interaction between highly electron deficient hydrogen and highly electronegative atom is called
(a)
Two fluorine atoms share one electron each in their outermost shell to achieve electronic configuration of:
(d)
Number of electrons lost by atoms of group IIIA equals:
(c)
Atom which loses two electrons from its outer shell to form ion is:
(c)
In NaCl crystal lattice each Na⁺ ion is surrounded by:
(a)
At room temperature most of ionic compounds are:
(b)
Tendency of atoms to acquire eight electrons in their valence shell is:
(a)
When one atom forms cation by losing electron and other forms anion by accepting that electron then bond form between them is:
(b)
Noble gases are stable because they contain:
(c)
Bond which involve 3 shared electron pairs is a:
(c)
A non-metal atom form anion by
(b)
When two identical atoms share electron pairs and exert same force on each other than bond form is:
(a)
Synthetic resins are used on places where:
(b)
Oxygen belongs to group VIA so number of electrons in its valence shell are:
(c)
Electron pairs which are not shared by atoms are called:
(b)
Strength of intermolecular forces from ionic or covalent bond is:
(a)
Ionic crystals have:
(a)
Bond formed by mutual sharing of electron is:
(c)
Which of the following diagram shows atoms are bonded with same electro negativity?
(a)
Why do atoms form chemical bonds?
Atoms form chemical bonds to achieve stability by attaining the electron configuration of noble gases (octet or duplet rule).
The noble gas electronic configuration is:
Noble gases have completely filled valence shells with the configuration ns² np⁶ (except He which has 1s²).
The octet rule states that atoms tend to have ___ electrons in their valence shell.
The octet rule states that atoms tend to gain, lose, or share electrons to achieve 8 valence electrons (except H and He which follow the duplet rule).
Helium follows the ___ rule because it has ___ valence electrons.
Helium has only 2 electrons in its valence shell (1s²) and thus follows the duplet rule for stability.
Valence electrons are located in the:
Valence electrons are the electrons in the outermost shell of an atom and are responsible for chemical bonding.
In the formation of NaCl, sodium loses ___ electron(s).
Sodium (Group IA) has 1 valence electron and loses it to form Na⁺ ion.
The force holding Na⁺ and Cl⁻ together in NaCl is:
Oppositely charged ions (Na⁺ and Cl⁻) are held together by strong electrostatic forces in ionic bonds.
A single covalent bond involves the sharing of ___ pair(s) of electrons.
A single bond (e.g., H-H) involves 1 shared pair (2 electrons).
Which molecule has a triple covalent bond?
N₂ has a triple bond (N≡N) with 3 shared electron pairs.
A double covalent bond is represented by:
Double bonds (e.g., O=O) are represented by two lines (=).
A polar covalent bond occurs when:
Polar bonds form when electrons are unequally shared due to electronegativity differences (e.g., H-Cl).
Which of the following is a polar molecule?
HCl is polar due to the electronegativity difference between H (2.1) and Cl (3.0).
A coordinate covalent bond is formed when:
In coordinate bonds (e.g., NH₄⁺), one atom provides both shared electrons.
The bond in NH₄⁺ involves:
The H⁺ ion forms a coordinate bond with the lone pair on N in NH₃ to form NH₄⁺.
Metallic bonding is due to:
Metals have a "sea of delocalized electrons" that move freely between positive metal ions.
Which intermolecular force is the weakest?
Dipole-dipole forces (between polar molecules) are weaker than ionic/covalent bonds or hydrogen bonds.
Hydrogen bonding occurs between hydrogen and:
H-bonding requires H bonded to highly electronegative N, O, or F atoms.
The melting point of NaCl is high because:
Strong electrostatic forces between Na⁺ and Cl⁻ ions require high energy to break, resulting in a high melting point (801°C).
Covalent compounds are generally:
Most covalent compounds (e.g., CH₄) are insoluble in water but soluble in non-polar solvents.
Which of the following is a non-polar molecule?
CO₂ is non-polar because its linear shape cancels out the dipole moments of the C=O bonds.
Metals are good conductors of electricity due to:
Metals conduct electricity because their delocalized "sea of electrons" can move freely.
The bond in H₂ is:
H₂ has equal electron sharing between identical atoms, making it non-polar covalent.
Which group of elements tends to gain one electron to form anions?
Halogens (Group VIIA) gain 1 electron to achieve octet (e.g., Cl → Cl⁻).
The electronegativity difference for a purely ionic bond is:
Ionic bonds form when electronegativity difference exceeds 1.7 (e.g., Na-Cl ΔEN = 2.1).
The bond in H₂O is:
O-H bonds are polar due to electronegativity difference (O: 3.5, H: 2.1).
Which of the following is NOT a noble gas?
Chlorine (Group VIIA) is a halogen, not a noble gas.
The bond in MgO is:
MgO forms when Mg²⁺ and O²⁻ ions bond electrostatically (ΔEN = 2.3).
Which of the following is a property of ionic compounds?
Ionic compounds conduct electricity when molten/aqueous because ions are free to move.
The bond in Cl₂ is:
Cl-Cl bond is non-polar due to equal electron sharing between identical atoms.
Which of the following is an example of a hydrogen bond?
H-F shows hydrogen bonding (H bonded to highly electronegative F).
The bond in NH₃ is:
N-H bonds are polar due to electronegativity difference (N: 3.0, H: 2.1).
Which of the following is a property of metals?
Metals are malleable (can be hammered into sheets) due to mobile electrons.
Which of the following is a characteristic of covalent compounds?
Covalent compounds lack free ions/electrons, making them poor conductors.
The bond in C₂H₂ (ethyne) is:
Ethyne (HC≡CH) has a triple bond between carbon atoms.
Which of the following is a use of epoxy resins?
Epoxy resins are widely used as strong adhesives in construction and manufacturing.