first year chemistry key points
MIX
FIRST YEAR
1.
The
sum of mole frictions of solute and solvent is always is equal to 1 or 1.0
2.
One
mole is the amount of substance which contain as many element particles as
there are in 0.012kg of C-12
3.
The
solids in which the molecules or ions are arranged in a regular repetitive
manner are called crystals
4.
The
α bond between carbon and oxygen atoms in aldehyde and ketone due to overlap of sp2-sp
5.
The
ionization potential of hydrogen atom is 13.6
V
6.
The
melting point and boiling point of ionic solids are High
7.
If
radius of circle become half keeping other quantities constant, then percentage
change in centripetal force is 100%
8.
The
London dispersion forces are present in polar and Non polar molecule
9.
The
frequency of electromagnetic do not change in Vacume
10.
If
electron moves from 1 to 2 orbit , the radius of orbit will increase 4 times
11.
The
first law of thermodynamics has a statement which implies that Energy is conserved
12.
The
bond in NaH is Ionic bond
13.
Liquids
crutals are Isotropic
14.
Because
of regular and well ordered arrangement crystalline solids are Anisotropic
15.
Crystalline
solids are also called True solids
16.
Amorphous
solids are also called Super cooled
liquids
17.
In
the periodic table, period represent The
number of shells in an element
18.
In
the periodic table, group represents Number
of outermost shell electrons
19.
The
wavelength of radio waves > microwaves > IR > VL > UV > X-rays
>Gamma rays
20.
The
weight of the molecules exerts a force on the wall of the container is cause of
exerting pressure by Ideal gas
21.
The
precipitation of AgCl will occur if ionic product is More than Ksp
22.
Number
of hydrogen atom presents in one mole of water is 1.204 x1024 atoms
23.
Charge
on one electron 1.6022 x 10-19 C
24.
Number
of electrons in one coulomb of charge is 6.25
x 1018
25.
If
Kc for certain reaction is large it indicates that Product concentration will be high
26.
AlCl3
is Lewis acid
27.
Forces
controlling the reaction are proportional to the product of active masses The law of mass action
28.
Hydrogen
bond in possible in NH3
29.
Most
stable covalent hydride HF
30.
At
constant temperature when volume of given mass of gas is doubled its density
becomes Half
31.
In
all reversible process the entropy of the system Increases
32.
0.1000
Mole of NaCl is dissolved in 1.000dm3 distilled water at 298K, the
concentration of resulting solution is 0.1000
M
33.
Mosely
derives a direct relationship between the frequency of x-rays emitted by an
element bombarded with high energy electrons, on what characteristic of the
element does it depend Atomic
number
34.
The
intensity of x-rays depend upon nature of material
of target
35.
The
charge of electron was determined by R
Milliken
36.
The
e/m ratio of an electron was determined by J.J
Thomson(1897)
37.
Metals
are good conducters because It has free electrons
38.
The
energy of electron in shell is given by En
=-1312/n2
39.
The
number of electron in one coulomb of charge are 6.25
x 1018
40.
The
solubility of solute depends upon Pressure, Temperature, nature of solute And solvent
41.
Heat
capacity of substance at constant volume is directly related to the Internal energy
42.
The
number of orbitals in “M” shell of an orbit is 9
43.
H2
most closely represent Ideal gas
44.
At
constant temperature, the pressure of the gas is doubled its volume becomes One half
45.
Angular
acceleration in the body is produced by Torque
46.
The
span of broad depends upon jumper’s Angle
of projection
47.
Evaporation
occurs at All temperature
48.
The
rate of reaction is defined as Dc/dt
49.
According
to bronsted and lowery concept SO4-2 cannot function as acid
50.
When
electron jump from one shell to another it emits energy, it was said by Bohr
51.
equal
volume of all gases at same temperature and pressure contain same number of
particles Avogadro’s law
52.
NCl3
contain Six bonded electrons
53.
An
orbital may never be occupied by 3
electrons
54.
Glass
in an example of amorphous solid which can be characterized as Very viscous fluid
55.
Four
balloons filled with different gases, hydrogen filled balloon flew High
56.
During
redox reaction an oxidizing agent Gain
electrons
57.
The
penetrating power of x-rays depends on Operating
voltage
58.
1s
2s 2p 3s 3p 4s 3d 4p 5s 4d 5p………… electronic
configuration
59.
The
paramagnetic nature of substance depends on number of Unpaired electrons
60.
The
value of Kc is different at Different
temperature
61.
Standard
solution are prepared in Volumetric flask
62.
Nitrogen
has three unpaired electrons according to Hund’s
rule
63.
Standard
hydrogen electrode may act as both cathode
and anode
64.
Stoichiometric
calculation based on chemical equation provides us estimation about Theoretical yield
65.
The
phenomenon of gas cooling by sudden expansion is called Joule Thomson Effect
66.
Both
hydrogen and helium is same number of Shells
67.
CO2
is iso-structural with C2 H2
68.
CaCO3
,CaC ,KCN are Inorganic
69.
(NH2)CO
is Organic
70.
Molecules
of oxygen is diatomic and behaves as paramagnetic
71.
HClO4
is strongest Acid from HClO1 ,
HClO2 , HClO3
72.
TiCl4
is use as catalyst for the manufacture
of ammonia
73.
The
shapes or appearance in which crytal grows is called Crystal habit
74.
SO2
is responsible for the formation of Acid
rain
75.
A
catalyst is more effectivne when it is in the finally divided state because It increase in surface area
76.
Electronic
configuration of an element is ns2 np2 it belongs to group 4th of periodic table
77.
CaCl2
anhydrous is use as Drying agent
78.
Water
boils at high temperature than HF because Hydrogen
bonding per molecule in H2O is greater than HF
79.
An
atom has net charge of -1 it has 18 electrons and 20 neutrons.it mass number is 37
80.
The
ionization energy of hydrogen atom is 13.6ev. the ionization potential require
will be 8.5 x 10-10 volt
81.
Elements
having same chemical properties belongs to same Group
(3,11)
82.
The
oxidation number of Cl in Ca(ClO3 )2 is +5
83.
Trade
name of titraflora ethylene polymer is Teflone
84.
Sum
of number of neutrons and protons are called Mass
number
85.
Water
at 40 C is Heaviest
86.
The
most electronegative element is found in period 2
87.
The
bond present in solid mercury is Metallic
bond
88.
Substance
dissolved in water react better because water Dissolves
them in ions
89.
4.0
dm3 of O2 at a pressure 800 atm and 1dm3 of N2 at pressure of 100 atm are put
in 2 dm container, the total pressure is 900
atm
90. The amount of
heat required the temperature of 1 calorie of substance through 1 K is called Heat capacity
91. The group of
animals which can run fast is Digitgrade
92. NaCl does not
conduct Electric current
93. The bonds
present in NH4 Cl are Ionic, Covalent and
co-ordinate covalent bond
94.
In
PV=nRT here n is number of
moles
95.
London
dispersion forces are present in Solid,
liquid and gases
96.
Stability
of ionic compound is due to Lattice
energy
97.
The
excited state of an atom which can persist for unusual longer time is Metastable state
98.
A
zero order reaction is one whose rate is independent of Reactant concentration
99.
If
the distance between two charged particle is halved. The coloumb’s force
between them becomes Four times
100.
The
neutralization of strong acid by a strong base liberates an amount of
energy per mole of H+ ion that is Always the same
101.
Spreading
of smell in room is due to diffusion
102.
A
well stoppered thermos flask containing some ice cubes is an example of Isolated system
103.
NH3
and HCl are present at both side of pipe and diffuse to react and form NH3 Cl ,the NH3 Cl will form
near the HCl end
104.
Vapor
pressure of mercury is less than Restified spirit, kerosene oil and Water
105.
A
concentrated solution has got High
solute potential
106.
Molecular
formula of an acid C H2 O is C2 H4 O2
107.
The
best known fuel cell is the hydrogen/ oxygen fuel cell. This is known as Bacon cell
108.
CO2
is non-polar but contained Polar bonds
109.
The
emf from galvanic cell can be calculated from The
E0 value of the half cell
110.
A
liquid is in equilibrium with its vapors at its boiling point. On the average
the molecules in the two phase have equal Total
energy
111.
Reason
for alkali metals to be soft is that, they have Not closed packed structure
112.
If
the pressure and temperature of 2 litres of CO2 are doubled, the volume will
become 2 litres
113.
Atoms
present in one mole of Ca(OH)2 are 5
x 6.023 x 1023 atoms
114.
Aluminum
is resistant to Corrosion
115.
CH4
&SiH4 have same Structure
116.
A
mixture of 50g H2 and 50 He has a total pressure of 1.5atm. partial pressure of
H2 gas is 1.0 atm
117.
Calculate
the volume occupied by 2.8g of nitrogen gas at STP is 22.4dm3
118.
A
piece of wood and iron seen to lose the same weight when completely submerged
in liquid. The two pieces must have the same Volume
119.
A
solution of 2,0g NaOH dissolved in 1000 g of water has concentration 0.05M
120.
Bohr’s
theory explains He+, Li++, Be+++
121.
The
oxidation number of hydrogen in metal hydrides -1
122.
In
discharge tube Neon gas will produce Pink
colour
123.
The
value of principle quantum number l=1,the value of magnetic quantum number(m)
are -1,0,+1
124.
The
study of heat changes accompanying a chemical reaction is known as Thermo-chemistry
125.
On
complete oxidation , one mole of an organic compound gave four moles of water
which is Propane
126.
Water
is not used as thermometric liquid because it does not Expand linearly
127.
Number
of moles of NaCl in 75,0g of table salt 1.28
128.
Oxygen
atom has two unpaired electrons it is there fore Paramagnetic
129.
The
sample of compound contain 0.100g of hydrogen and 4.20g of nitrogen , the
compound is NH3
130.
Hybrid
orbitals used by carbon atoms in C H4 is Sp3
131.
Hybrid
orbitals used by carbon atoms in C2 H4 is Sp2
132.
Hybrid
orbitals used by carbon atoms in C2 H2 is Sp
133.
Esters
are represented by general formula RCOOR
134.
Ag2
S is a Not common occurring sulphur
compound
135.
Theoretical
yield is always less than actual yield because of Reversibility, Side reaction, Mechanical loss, Human error
