Which best describes the bonding between Mg and Cl?
Mg and Cl form covalent bonds by sharing of electron pairs
There is a lattice of positive ions in a sea of delocalised electrons
Polyatomic ions exhibit covalent bonding between the atoms within the ion
The atoms readily form ions which are attracted to each other
Which one of the following statements about dispersion forces in a series of molecules is correct?
An increased molecular weight leads to a greater mass of the molecule and hence stronger dispersion forces
An increased number of protons and electrons leads to stronger dispersion forces
Larger electronegativity differences lead to stronger dispersion forces
The presence of an atom such as O or N bonded to H leads to stronger dispersion forces
Which statement best describes a covalent bond?
There is greater attraction of electrons to the more electronegative atom
There is simultaneous attraction of both nuclei to a shared electron pair
The atoms have a noble gas electron configuration
The atoms have formed an infinite network
Consider the following structures
Which of the following statements is true?
None of I, II and III are ions
I and III are ions
II and III are ions
I and II are ions
Which one of the following is true of the atoms of a given element?
The number of protons must be greater than the number of neutrons
The number of protons must be equal to the number of neutrons
The number of neutrons must be greater than the number of electrons
The number of protons must be equal to the number of electrons
For an element X, the first five successive ionisation energies can be represented on the following graph.
What would be the formula of the compound formed when X reacts with chlorine?
XCl3
XCl2
XCl
XCl4
An element has the first five successive ionisation energies as shown on the graph.
Which one of the following is it?
calcium
neon
carbon
aluminium
Which one of the following descriptions best applies to the term ' valence electrons'?
electrons in the s and p orbitals
electrons in the outer energy level
electrons which make up a noble gas electron configuration
electrons which are lost when bonds form
An element 'X' forms a chloride XCl3. Which can not be X?
N
Fe
Sr
Al
Which of the following will have the highest melting point?
silicon dioxide
sulfur dioxide
carbon dioxide
nitrogen dioxide
An element Y has the electron configuration 1s22s22p5 and forms a compound XY2 with element X. Which one of the following could be the electron configuration of X?
1s22s22p63s1
1s22s2
1s22s22p1
1s22s22p2
Which of the following elements has the lowest first ionisation energy?
Be
B
Mg
K
Which one of the following species has a different number of electrons from all the others?
Ar
Cl-
Ca2+
Al3+
Which one of the following lists the attractive forces in decreasing order (strongest to weakest)?
The table below gives information about three pure solids designated X,Y and Z.
X
Y
Z
Approximate Melting Point oC
800
3500
1500
Electrical Conductivity in the solid state
nil
moderate
High
Electrical conductivity in the liquid (molten) state
high
cannot be easily treated
high
Which one of the following describes the bonding present in the three substances?
X is ionic, Y is covalent network, Z is metallic
X is ionic, Y is metallic, Z is metallic
X is covalent molecular, Y is metallic, Z is ionic
X is covalent molecular, Y is covalent network, Z is ionic
Which of the following is the electron configuration of N3-?
1s22s22p3
1s22s2
1s22s22p6
1s22s22p63s23p1
How many valence electrons are present in a nitrite ion NO2-?
1
18
17
24
Which one of the following compounds contains only ionic bonds?
CH3OH
NaNO3
NaH
HCl
Which one of the following compounds contains only covalent bonds between its atoms?
CO2
NH4Cl
NaCl
KNO3
Which of the following arranges the substances in order of increasing ionisation energy?
none of the given answers
F < S < Si < Mg
Mg < S < Si < F
F < Mg < Si < S
Consider the following set of successive ionisation energies (MJ mol-1).
0.74 ; 1.45 ; 7.73 ; 10.54 ; 13.63
Which of the following elements is most likely to have such a set of ionisation energies?
K
O
Mg
C
Which one of the following determines which element an atom will be?
Its number of neutrons
Its number of protons
Its electron configuration
Its electric charge
Which of the following has the highest first ionisation energy?
Si
Mg
S
F
Which one of the following statements is true?
H2O has a greater molecular polarity (dipole moment) than H2S
The molecules H2S and H2O are both linear
H2O is polar, but H2S is non-polar
The molecules H2S and H2O both have zero molecular polarity (dipole moment).
Which one of the properties of ammonia is not related to the hydrogen bonding between the molecules?
vapour pressure
molar mass
solubility in water
freezing point
Which one of the following statements about graphite and diamond is true?
They have the same crystal lattice structure
They have the same degree of hardness
They can undergo the same chemical reactions
They have the same electrical conductivity
Which of the following 1.00 mol L-1 aqueous solutions will conduct electricity?
I hydrogen chloride II ethanol III ammonia IV sodium nitrate
IV only
I, II and IV only
I, III and IV only
I and IV only
Which one of the following may have 17 protons, 19 neutrons and 18 electrons?
K+
K
Cl
Cl-
Which one of the following may have 19 protons, 21 neutrons and 19 electrons?
K
Ar
Sc
K+
Which one of the following electron configurations represents an element that forms a monoatomic ion with a charge of -2?
1s22s22p6
1s22s2
1s22s22p2
1s22s22p4
Species 'X' has the valence electron configuration of s2, and 'Z' has the valence electron configuration of s2p5. Which of the following is the most likely formula of a compound formed between 'X' and 'Z' ?
XZ
X2Z5
XZ2
X2Z7
Element A has the valence electron configuration of s2 and element B has the valence electron configuration of s2p5. What will be the most likely formula of the compound formed between the two elements?
AB3
AB2
A2B
AB
How many orbitals can be found in the d subshell of the 3rd principal energy level?
3
8
5
10
On which one of the following does the type of bond formed between two atoms depend?
Their atomic weights
The electrical conductivity of the compound
Their electronegativities
The melting and boiling point of the compound
In which one of the following substances is hydrogen bonding th main intermolecular force at room temperature?
hydrogen sulphide
hydrogen bromide
ethanol
methane
In the graphite crystal lattice, what is the number of nearest covalently bonded neighbours for each carbon atom?
4
6
3
5
Which of the following substances contains dispersion forces?
I CO2 II CH3CH2OH III SiO2
I and II only
I only
I, II and III
None of the given answers
In which one of the following is the solid state maintained only by covalent bonding?
CO2(s)
SiO2(s)
H2O(s)
NH4Cl(s)
Which one of the following ions does not have the electronic configuration 1s22s22p63s23p6 ?
Br-
S2-
Ca2+
Cl-
What is the maximum number of unpaired electrons possible in 3d orbitals?