Atomic structure and bonding
Moving from left to right across a period, the general rise in the first ionization energy can be attributed to the
decrease in screening effect
increase in screening effect
decrease in nuclear charge
increase in nuclear charge
How many unpaired electron(s) are there in the nitrogen sub-levels ?
The maximum number of electrons in the L shell of an atom is
Elements in the same period in the periodic table have the same
number of shells
The reaction above illustrates
If an atom is represented as 2311X which of the following deductions is correct?
it contains 12 protons
it forms a covalent chloride
its atomic number is 23
it is an alkali metal
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
Cathode rays cause an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays
are positively charged
are negatively charged
travel in straight lines
Which quantum number divides shells into orbitals?
The type of bonding in [Cu(NH3)2]2+ is
16.8g of sodium hydrogen trioxocarbonate (IV) is completely decomposed by heat. Calculate the volume of carbon (IV) oxide given off at s.t.p?
[Na = 23, C = 12, O = 16, H = 1
Molar volume of a gas at s.t.p = 22.4 dm3]
The experiment that showed that atoms have tiny positively charged nucleus was first carried out by
The atom of an element X is represented as YZX. The basic chemical properties of X depend on the value of
Y - Z
Z - Y
In the periodic table, electrical and thermal conductivities are properties of elements that
decrease across the period and increase down the group
increase across the period and decrease down the group
decrease across the period and down the group
increase across the period and down the group
The reaction above is an example of
The type of isomerism shown by cis-and transisomers is
A metal X forms two bromides with the formula XBr2 and XBr3. What type of bonding exists between X and bromine in the bromides?
How many electrons are in the L shell of 3115P?
Which experiment led to the measurement of the charge on an electron?
Scattering α - particles
Mass spectrometric experiment
If the electronic configuration of an element is 1s2 2s2 2p5, how many unpaired electrons are there
The element that belongs to the third period of the periodic table are
B, C, N and O
Na, Mg, S and Ar
Li, Be, Al and P
Na, P, O and Cl
The efficiency of a solid catalyst to increase reaction rates depends on its
Which of the following pairs of substances will react further with oxygen to form a higher oxide
CO2 and H2O
NO and H2O
CO and CO2
SO2 and NO