CHEMISTRY-Obj!-
1EECBBAEBBB
11DDDBEAEABB
21DBECCDAAAB
31BADCBACDAC
41CECCEADBDC
51CEBEEDDBAE

Completed!.
====================================








====================================

====================================


Chemistry-THEORY
(4a) 
(i)Enthalpy of combustion can be defined as the amount of heat evolved when one mole of a substance burns in air or oxygen

(ii) Isomerism can be defined as a phenomenon in which organic compounds are having the same molecular formula but different structural formula

(4bi) 
NO2 - Acidic oxide
CO - Neutral oxide 
Fe2O3 - Basic oxide
Al2O3 - Amphoteric oxide 

(4bii)
(i)Nitrous oxide
(ii)Carbon (iv) oxide

(4c)
(i) Fractional distillation of liquid air 

(ii) 2KNO3 -----> 2KNO2(s) + O2(g)

(NH)CO3(s) ------>2NH3(g) + CO2(g) + H2O(g)

(iii) No. of molecules = 4/16 × 6.02 × 10²³
= 1.5 × 10²³

(4di)
(i)Sodium
(ii)Potassium

(4dii)
(i)Carbon (iv) oxide
(ii)Carbon

(4diii) 
(i)Hydration
(ii)Oxidation
====================================

(5ai)
Gay Lussac's states that when gaese react, they do so in volume which bear a simple whole number ratio to one another and to the volume of their products.

(5aii) 
2CO + O2 ----> 2CO2
  2 1 2    
100cm³ 70cm³ 100cm³

Total volume = 100+70+100 = 270cm³

(5bi)
(i)It is used in the production of other chemical substances
(ii)It is used as a drying or dehydrating agent 

(5bii)
(i) ZnCO3 -----> ZnO + CO2

->Conditions<-
- High temperature
- High pressure
 
(ii) ZnO + H2SO4 ----> ZnSO4 + H2

->Conditions<-
- Catalyst
- Surface area

(5biii)
(i) Crystallization method
(ii) By heating the ZnSO4 with an alkali metal carbonate 

(5c)
(i) This is due to the presence of extra electrons not used for bonding graphite 
(ii) This is because sodium salts are soluble and double decomposition is used for the production of insoluble salts 
(iii) It is an alkali substance ie possesses basic properties

(5di)
(i)Bitumen coal 
(ii)Peat coal

(5dii)
Fractional distillation
====================================

(2ai) 
(i)Molecules of gases are in constant random motion
(ii)The collision of gases is perfectly elastic
(iii)An increase in temperature leads to an increase in the average kinetic energy of the molecules of gases

(2aii)
(i)They both turn blue litmus paper red
(ii)They both dissolve in water to produce an acid 

(2aiii) 
Copper

(2aiv)
Copper 

(2bi)
Activation energy can be defined as the minimum energy required for a reaction to occur.

(2bii)
Catalyst lowers activation energy

(2biii)
Nikel

(2biv) 
(i)Sodium trioxocarbonate (iv)
(ii)Hydrogen gas 

(2ci)
(i)It reacts with metals to liberate hydrogen
(ii)It reacts with base to produce salt and water only

(2cii)
(i) 2KI + 2Cl2 ----> 2Kl2 + I2

(ii) 2Zn + Cl2 -----> 2ZnCl

(2ciii)
Cl2

(2civ)
Covalent bond

(2d)
(i) Butane 
(ii) Propene
(iii) Ethanol
(iv) Ethyne
====================================

(1ai)
(i) Base has bitter taste 
(ii) Base is soapy to touch 
(iii) Base turns litmus paper blue

(1aii)
The steps involved are:
(i)Shift conversion
(ii)Removal of carbon (iv) oxide
(iii)Steam reforming

(1aiii)
Cracking is the process by which heavier hydrocarbon molecule is splitted into two or more lighter molecules

(1aiv)
Thermal cracking

(1bi)
P ion = 1s²2s²2p⁶

(1bii)
Formula of chloride is Pcl2

(1biii)
Reducing agent
This is because it undergoes oxidation by losing electrons

(1ci)
Electron affinity is the energy released when a gaseous atom gains an electron to form a gaseous negative ion.

(1cii)
This is because it has lone pairs of electrons 

(1di)
(i) By adding a catalyst

(ii) FeS(s) + 2HCl(g) -----> FeCl(g) + H2S(s)

Xg = ?
No. of FeCl2 = 127g/mole
No. of FeS= 88g/mole

Mole = Mass/ No. of Mass = 3.2/127 = 0.025mole of FeCl2

By comparison,
1 mole of FeS = 1 mole of FeCl2
X moles of FeS = 0.025 of FeCl2
X = 0.025mole of FeS

Recall,
Mass = Mole * molar mass
Mass = 0.025*88
Mass = 2.2g of FeS
X = 2.2g

(1dii)
(i)Chlorofluorocarbons
(ii)Ammonia
====================================

Completed!. We Remain The baddest 
Site Ever.



17a


-electric incandescent light bulb or other light source (usually fan-cooled)

-reflector and "condensing" lens to direct the light to the slide.

- slide holder.

- focusing lens.
===========
 (8a)

*Lost volt:* The potential difference between the two terminals of a cell decrease by an amount that does not contribute to the circuit, is called lost volt.
===========
 13a.

 *Elastic Collision* 
An elastic collision can be defined as a state where there is no net loss in kinetic energy in the system as the result of the collision.


 *Inelastic Collision* 
An inelastic collision can be defined as a type of collision where this is a loss of kinetic energy. The lost kinetic energy is transformed into thermal energy, sound energy, and material deformation.

===========
 14a.
- Snell's law of refraction states that “The ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant for a given pair of media and given wavelength of light.” The constant in law is called refractive index and denoted by the letter 'n'.

===========

 (12ai)
Fundamental quantity: quantities which are independent on other physical quantity. eg length, mass, time, current, amount of substance, luminous intensity, thermodynamic temperature

===========

 6a)
A wave front is the locus of points characterized by
propagation of position of the same phase: a propagation
of a line in 1D, a curve in 2D or a surface for a wave in
3D. In other words a line or surface in the path of an
advancing wave on which all the particles are vibrating in
phase is called a wave front.

(1b)
Tabulate

- Simple Microscope it is used for reading small prints and for studying biological specimens.
- The magnifying glass or simple microscope is a convex lens which is used to produce magnified images of small object.
- When a converging lens is used as a simple microscope the object is placed between the principal focus and the optical center of the lens.

- The Compound microscope consists of two converging lenses of short focal lengths.  
- To produce a higher magnification that obtained from a simple microscope.

(1c)

A simple microscope uses the optical power of single lens or group of lenses for magnification *While*; A compound microscope uses a system of lenses (one set enlarging the image produced by another) to achieve much higher magnification of an object.






Post a Comment

 
Top