s & p elements Flashcards
Potassium can displace Na from NaCl due to
Potassium is more electropositive than Na, so it displace Na from compounds
Sodium burns in chlorine with __________ flame.
orange
1s orbital contributes to maximum screening in:
Iodine has smallest is orbital in all due to greatest nuclear charge on it. So its contribution in screening is maximum.
Which elements can form more than 5 bonds normally?
Iodine can form upto 7 bonds due to hyper valance as in IF7.
Which one of the following properties of IIA group elements increases down the group?
reducing power of IIA group elements increase down the group and electropositivity and reactivity. As a result ionization energy decreases and metallic character increases.
Which orbital contributes least to screening of electron?
f – orbital is least penetrating so its screening is least.
Excess methane reacts with chlorine. The major product is
Chloromethane
In excess alkane, monosubstituted product is favored.
In limited alkane, tetrasubstituted product is favored.
In heterocyclic compounds, the heteroatom might be
O, N or S.
Ionic bond is formed by elements having:
↓ polarizing power ↓ polarizability
What is the value of second electron affinity of oxygen?
+780 KJ/mol
The heat of hydration of alkaline earth metals ____ down the group.
Decreases
The charge density of alkaline earth metals decreases down the group. Therefore the attraction of ions and water is decreased i.e. heat of hydration decreases.
Li lies at the top of electrochemical series due to:
High hydration energy
trend of ionization energy in periodic table
I.E:- ↑ along period, ↓ down the group
Trend along period: GI < GII > GIII < GIV < GV > GVI < GVII < GVIII
The oxides of beryllium are
amphoteric
which oxides are amphoteric in nature and why
Oxides of relatively less electropositive elements such as Be, Al, Bi and Zn are amphoteric in nature.
Lithium combines with nitrogen directly to form
lithium nitrides
Li3N
red pink color
What is the symbol of the element with only 5 electrons and 5 protons?
boron
why do we call group 2 elements alkaline earth metals
(i). They give alkalis in water.
(ii). Exist abundantly on earth crust in form of carbonates and silicates
f-block elements are also called
Inner transition elements
The f-block elements are the lanthanides and actinides and are called the inner transition elements because of their placement in the periodic table due to their electron configurations.
In these elements, three outermost shells are not completely filled. The last electron in them enters in the (n-2) subshells.
After hydrogen and helium, the smallest element in the periodic table is?
Flourine
Most important commercial source of lithium is
Spodumene is LiAl(SiO₃)₂(Lithium aluminium silicate)
The property which increases upto group IV-A then decreases onwards
mp and bp
The milk of magnesia MgOH2 is used for the treatment of
acidity
Most electropositive element of the periodic table is
Cs
In second period of periodic table, number of elements belong to “p” block are
6
Carbonate of ________ is least soluble in IA group.
lithium
Sodium metal cannot be stored under
polar solvents like alcohol
Na metal is very reactive so it is stored in non-polar solvent like hexane, benzene and kerosene.
trend of electrical conductance
Electrical conductance increases from IA to IIIA.
Caustic Soda is
Deliquescent
What is the electronic configuration of Cs?
[Xe] 6s1
the hydrides of Be and Mg are classified as intermediate hydrides. their behavior is :
polymeric and covalent in nature
potassium is found in nature as carnalites its composition is
KCl.MgCl2.6H2O
calcium is found in nature as CaSO4(2H2O). this is commercially called
gypsum
fajans rule states that small highly charged ions tend to form more:
covalent compounds
reason for alkali metals to be soft is that
there is only one valency
which oxide sodium predominantly forms in oxygen
Na2O2 (pale yellow)
sodium peroxide
molecular formula of silica
SiO2
sodium carbonate when fused with sand forms sodium silicate which is commonly known as
water glass
when Pb shows inert pair effect it always form
ionic bond
electron affinity trend
First electron affinity is mostly exothermic while second electron affinity is usually endothermic.
Additional Information:
E.A in groups:
I > II < III < IV > V < VI < VII > VIII
e.g. Na > Mg < Al < Si > P < S < Cl > Ar
