t2 cram Flashcards
name the following: short form of an element
symbol
name the following: the number of hydrogen atoms which can combine with or displace one atom of the element or radical so as to form a compound
valency
what is the valency of all metals
positive
what is the valency of non metals
negative
name the following: a group of atoms of elements that behave like a single unit and shows a valency
radical
name the following: representations of a substance
chemical formula
valency of potassium
K 1+
valency of sodium
Na 1+
valency of carbide
C 4-
valency of nitride
N 3-
valency of hydrogen
H 1+
valency of chloride
Cl 1-
valency of phosphite
PO3 3-
valency of aluminium
Al 3+
valency of phosphate
PO4 3-
valency of chromium
Cr 3+
valency of sulphite
SO3 2-
valency of ammonium
NH4 1+
valency of calcium
Ca 2+
valency of magnesium
Mg 2+
valency of zinc
Zn 2+
valency of chlorate
ClO3 1-
valency of hypochlorite
ClO 1-
valency of lithium
Li 1+
valency of barium
Ba 2+
valency of nickel
Ni 2+
valency of sulphate
SO4 2-
valency of cobalt
Co 2+
valency of sulphide
S 2-
valency of carbonate
CO3 2-
valency of uranium
U 2+
valency of bromide
Br 1-
valency of iodide
I 1-
valency of hydroxide
OH 1-
valency of oxide
O 2-
valency of nitrite
NO2 1-
valency of chromate
CrO4 2-
valency of dichromate
Cr2O7 2-
valency of peroxide
O2 2-
valency of nitrate
NO3 1-
valency of hydrogen bicarbonate
HCO3 1-
valency of hydrogen bisulphite
HSO3 1-
valency of silicate
SiO3 2-
valency of aluminate
AlO2 1-
valency of zincate
ZnO2 2-
valency of plumbite
PbO2 2-
valency of hydrogen bisulphate
HSO4 1-
valency of permanganate
MnO4 1-
valency of cupric
Cu 2+
valency of cuprous
Cu 1+
valency of argentous
Ag 1+
valency of argentic
Ag 2+
valency of mercurous
Hg 1+
valency of mercuric
Hg 2+
valency of aurous
Au 1+
valency of auric
Au 3+
valency of ferrous
Fe 2+
valency of Ferric
Fe 3+
valency of plumbous
Pb 2+
valency of plumbic
Pb 4+
valency of stannous
Sn 2+
valency of stannic
Sn 4+
valency of Manganous
Mn 2+
valency of manganic
Mn 4+
valency of platinous
Pt 2+
valency of platinic
Pt 4+
what is the formula of nitric acid
HNO3
formula of sulphuric acid
H2SO4
formula of carbonic acid
H2CO3
formula of phosphoric acid
H3PO4
formula of acetic acid
CH3COOH
formula of gypsum
CaSO4. 2H2O
formula of blue vitriol
CuSO4. 5H2O
formula of epsom salt
MgSO4. 7H2O
formula of green vitriol
FeSO4. 7H20
formula of glaubers salt
Na2SO4. 10H20
formula of washing soda
Na2CO3. 10 H2O
what is the formula of methane
CH4
formula of ethane
C2H6
formula of propane
C3H8
formula of butane
C4H10
formula of methanol
CH3OH
formula of ethanol
C2H5OH
formula of propanol
C2H7OH
name the following: the number of times one atom of an element is heavier than 1/12 the mass of an atom of carbon
relative atomic mass
name the following: the number of times one molecule of the substance is heavier than 1/12 the mass of an atom of carbon
relative molecular mass
what is the formula of tetra amine zinc sulphate
[Zn(NH3)4]SO4
tetra amine copper 2 sulphate formula
[Cu(NH3)4]SO4
diamine silver chloride formula
[Ag(NH3)2]Cl
the force which acts between two or more atoms to hold them together as a stable molecule is called a ____
chemical bond
the chemical bond formed by transfer of electrons from the atom of a metallic element to an atom of a non metallic element is called____
electrovalent bond
the chemical bond formed due to the mutual sharing of electrons is called
covalent bond
what are 4 characteristics of chemical reactions
change of colour
evolution of a gas
formation of a precipitate
evolution or absorption of heat
list an observation in the heating of copper 2 nitrate
blue copper 2 nitrate turns into black copper 2 oxide
list an observation of heating on lead 2 nitrate
white lead 2 nitrate turns into yellow litharge
what is the reaction of sodium sulphite with dilute sulphuric acid
Na2SO3 + H2SO4 -> Na2SO4 + H2O + SO2
what is the reaction of calcium carbonate with dilute hydrochloric acid
CaCO3 + 2HCL -> CaCl2 + 2H2O + 2NH3
what is the reaction of ammonium chloride with calcium hydroxide
CaCl2 + 2H2O + 2NH3
what effect does carbon dioxide have on KMnO4 paper
no effect
what effect does carbon dioxide have on K2Cr2O7 paper
From orange –> green
what effect does so2 have on Pink KMnO4
it turns it colourless
what effect does ammonia have on litmus
Red –> Blue
what is the colour of lead chloride
white precipitate
what is the colour of copper 2 hydroxide
pale blue ppt.
what r the 4 types of reactions
synthesis, decomposition, displacement, double decomposition
list the metal reactivity series
please- Potassium stop- sodium calling- calcium me- magnesium a- aluminium careless- carbon zebra- zinc instead- iron try- tin learning- lead how- hydrogen copper- copper saves- silver gold- gold platinum- platinum
from where to where in the reactivity series are oxides stable to heat
K to Cu
what is the structure of Hg and Ag oxides in thermal decomposition reactions
metal + oxygen
what 2 hydroxides are stable to heat
K, Na
what is the structure of Ca to Cu hydroxide under heat
Metal oxide + water
which 2 carbonates r stable to heat
K, Na
what is the structure of Ca to Cu carbonate under heat
metal oxide + co2
what do K and Na nitrate give under heat
nitrite + oxygen
what do ca to cu nitrates give under heat
metal oxide + no2 + o2
what do hg and ag nitrites give under heat
metal + no2 + o2
what is the reaction of heat on ammonium dichromate
(NH4)2Cr2O7 –> Cr2O3 + 4H2O + N2
list an observation about Iron 2 hydroxide
Dirty green ppt.
is iron 2 hydroxide soluble
no
list an observation on Iron 3 hydroxide
reddish brown
is iron 3 hydroxide soluble
insoluble
list an observation on copper 2 hydroxide
pale blue ppt.
is copper 2 hydroxide soluble
insoluble
is zinc hydroxide soluble
yes
list an observation on zinc hydroxide
gelatinous white
list an observation on lead 2 hydroxide
chalky white ppt
is lead 2 hydroxide soluble
yes
which chemical reaction proceeds with evolution of heat energy
exothermic reaction
which chemical reaction proceeds with absorption of heat energy
endothermic reaction
which chemical reaction proceeds with absorption of light energy
photochemical reaction
why are silver salts kept in dark colored bottles
4AgBr –> 2Ag2Br + Br2 in the presence of sunlight
which chemical reaction proceeds with the absorption of electrical energy
electrochemical reaction
what is the universal solvent
water
why is water called the universal solvent
it has the ability to dissolve a large number of substances and gases
what is a homogenous mixture of a solute in a solvent
solution
what is a solution which can dissolve more of the solute at a given temperature
unsaturated solution
what is a solution which cannot dissolve more of the solute at a given temperature
saturated solution
list 2 ways a saturated solution can be converted to an unsaturated solution
- by heating the saturated solution slowly
- by adding more solvent
what is a solution which can hold more of the solute at a given temperature than that present in a saturated solution
super saturated solution
name a substance with which it is possible to cool a saturated solution without excess solute crystallizing out
Na2SO4. 10H2O
what is the maximum amount of the solute in grams that will saturate at a particular temperature
solubility
give an example of a solid which increases in solubility with rise in temp.
KNO3
give an example of a solid which increases slightly in solubility with rise in temperature
NaCl
give an example of a solid whose solubility decreases with rise in temperature
CaSO4
what is the process by which crystals are separated or deposited from a hot saturated solution of a substance on cooling gently called
crystallisation
rapid cooling of a hot saturated soln. results in the formation of _____
amorphous solids
what is the fixed number of water molecules which enters into a loose chemical combination with the substance when the substance is crystallised from its hot saturated solution called
water of crystallisation
what is responsible for the geometric shape and colour of the crystal
water of crystallisation
___ contains fixed number of water molecules
hydrated substance
___ does not contain any fixed number of molecules
anhydrous substance
give an example of a hydrated substance
CuSO4. 5H2O
give an example of an anhydrous substance
KNO3
list the reaction on the effect of heat on CuSO4.5H2O
CuSO4.5H20 -> CuSO4 + 5H2O
What is the structure of hydrous copper sulphate before and after heating
before : blue crystals
after : white powder
what is the the shape of hydrous copper sulphate before and after heating
Before : definite geometric shape
after: no geometric shape
what is the nature of hydrated copper sulphate before and after heating
crystalline, amorphous
what are crystalline hydrated salts which on exposure to the atmosphere lose their moisture partly or completely to it
efflorescent substance
what is the state efflorescent substances turn into
amorphous
what is the state deliquescent substances turn into
liquid state
what are water soluble salts which on exposure to the atmosphere absorb moisture from the atmosphere and dissolve in the moisture
deliquescent substances
give an example of efflorescent and deliquescent crystals
washing soda, calcium chloride
why is efflorescence minimum during humid conditions
this is because efflorescence occurs when the vapor pressure of the hydrated crystals exceeds the vapor pressure of the atmospheric humidity
why is deliquescence minimum during dry conditions
this is because deliquescence occurs when the vapor pressure of the atmospheric humidity exceeds the vapor pressure of the crystal solution
why does common salt turn moist on exposure to air
this is because it is not deliquiscent but contains a small amount of calcium and magnesium chloride impurities which are deliquescent
what is a substance which absorbs moisture from the atmosphere but does not change its state
hygroscopic subtance
list an example of hygroscopic substance
Quicklime [CaO]
what are substances which can readily absorb or remove moisture from other substances
drying agents
name a deliquescent drying agent
Fused Calcium Chloride
what remove chemically combined water or elements of water from compounds due to their strong affinity for water
dehydrating agents
what is hygroscopic drying and dehydrating agent
concentrated sulphuric acid
list a liquid hygroscopic substance
concentrated sulphuric acid H2SO4
who arranged elements in triands
dobereiner
why did law of triads fail, 2 reasons
the method didnt hold true for all elements
properties of elements in triads were not similar
who arranged elements in increasing order of weight in series of eights
new land
list 2 defects of newland
it failed to leave spaces for undiscovered elements
it failed with heavy metals beyond K
list 3 defects of mendeleefs table
- some pairs of elements having higher atomic weights have been given positions before the elements having lower atomic weights
- position of rare earths and actinides could only be justified if arranged according to their atomic numbers
- isotopes had to be placed in same position according atomic numbers.
list 6 contributions of mendeleed
elements were arranged in horizontal periods and vertical groups
elements with similar chemical properties are grouped together
elements in the same group had same valency and similar chemical properties
gaps were left in the table for undiscovered elements
incorrect atomic weights were corrected with the knowledge of adjacent elements atomic weight
properties of undiscovered elements left in the vacant gaps was predicted
list a difference between mosleys classification and mendeleefs contributions
most defects disappear if the basis of classification of elements is changed from atomic weights to atomic numbers
why do elements arranged in increasing order of atomic number show similarity in properties after regular internals
physical and chemical properties of elements are periodic functions of their atomic numbers
how many groups and periods r there
7 periods, 18 groups
what is the modern periodic table
mosleys classification
how are elements in periods arranged
in increasing order of atomic numbers
what do group numbers signify
valence electrons of an element
is iron reacting with steam irreversible
no, it is reversible
what is the reaction between iron and steam
3Fe + 4H2O -> Fe3O4 + 4H2
give an example of neutralization
NaOH + HCl -> NaCl + H2O
give an example of precipitation
CaCl2 + Na2CO3 -> 2NaCl + CaCO3
how is hydrogen gas collected in preparation of hydrogen by labratory method
downward displacement of water
what is the observation in preparation of hydrogen by action of dilute acid on zinc
a brisk effervescence is seen with the evolution of hydrogen gas
state the reaction in action of dilute acid on zinc
Zn + 2HCL [dil.] -> ZnCl2 + H2
what is the reaction in electrolysis of water
2H2O -> 2H2 + O2 with electric current on arrow
why is granulated zinc preferred in preparation of hydrogen
granulated zinc is obtained from molten zinc with traces of impurities of cu which has a slight catalyzing effect
list 2 precautions in preparation of hydrogen
- no leakage of gas should take place
- apparatus must be air tight as hydrogen forms explosive mixture with air
why cant nitric acid be used in preparation of hydrogen
it is a strong oxidizing agent to it does not yield hydrogen with metals as all the hydrogen gets oxidized to water
why cant we use lead in place of zinc in preparation of hydrogen
this is because lead forms a coating of salt on the metal and reaction stops
what are the three steps of bosch process
Production of water gas
reduction of steam to hydrogen by carbon monoxide
separation of carbon dioxide and unreacted carbon monoxide from the mixture
what is reaction for production of water gas
C + H2O -> CO + H2 - heat sign. Put 1000 degrees celsius above arrow
what is reaction for reduction of steam to hydrogen by carbon monoxide.
CO + H2 +H2O -> CO2 +2H2 + heat sign. put 450 degrees celsius and Fe2O3 on arrow
reaction for removal of co2
2KOH + CO2 -> K2CO3 + H2O
reaction for removal of CO
CuCl + CO + 2H2O -> CuCl.CO.2H2O
what do the following grps contain 1-2 3-12 13-17 18
reactive metals
transition elements
non metals
inert gases
what r the 4 types of oxidation
addition of oxygen
removal of hydrogen
addition of electronegative element
removal of electro positive element
what r the 4 types of reduction
removal of oxygen
addition of hydrogen
removal of electronegative element
addition of electro positive element
