Which ion is coloured Cu⁺ or Cu²⁺ ?

Cu in neutral state Z = 29

1S² 2S²2P⁶3S²3P⁶4S²3d⁹ which rearranges as 1S² 2S²2P⁶3S²3P⁶4S¹3d¹⁰

Cu⁺  1S² 2S²2P⁶3S²3P⁶4S⁰ 3d¹⁰

Cu²⁺ is 1S² 2S²2P⁶3S²3P⁶4S⁰ 3d⁹

Cu ²⁺ is coloured since d-d transition takes place in Cu²⁺ which has 3d⁹ in its electronic  configuration  whereas Cu⁺ has completely filled d orbital where such a transition is not possible.

Explain Ni Cd battery functioing.

The nickel–cadmium battery (NiCd battery or NiCad battery) is a type of rechargeable battery using nickel oxide hydroxide and metallic cadmium as electrodes. A fully charged Ni-Cd cell contains:

·         a nickel(III) oxide-hydroxide positive electrode plate

·         a cadmium negative electrode plate

·         a separator, and an alkaline electrolyte (potassium hydroxide).

The chemical reactions at the cadmium electrode during discharge are:

    Cd + 2OH^{−−                                                    Cd(OH)}₂ + 2 e⁻

            The reactions at the nickel oxide electrode are:

              2 NiO(OH) + 2 H₂O + 2 e⁻                                      2 Ni((OH)₂  + 2 OH⁻

             The net reaction during discharge is

             2NiO(OH)  + Cd + 2 H₂O                                2 Ni (OH)₂ + Cd(OH)₂

During recharge, the reactions go from right to left

Ni–Cd batteries contain between 6% (for industrial batteries) and 18% (for commercial batteries) cadmium, which is a toxic heavy metal and therefore requires special care during battery disposal. Cadmium, being a heavy metal, can cause substantial pollution when discarded in a landfill or incinerated

Major Features
Cost effective, Reliable safety vent system, Long service life,
Wide temperature range, Excellent permanent charge endurance
 

Major Applications
Lighting:                        Emergency lighting, Solar light, Flashlight
Toys:                              R/C cars, Racing cars, R/C ships
Communications:       Cordless telephone, Two-way radios
Electric Tools:              Electric Screwdrivers, Auto-mower, Portable vacuum cleaners
Audiovisual Devices:  Camera, MP3/MP4, Remote control, Portable DVD
Other Applications:      Shavers, Access controller, and so on

Explain the action of heat on alpha,beta and gamma amino acids
Alpha amino acid give di keto piperazine on heating
Beta amino acid give acrylic acid eliminating ammonia on heating
Gamma amino acid give inner amide or lactam
(Refer reactions of amino acids involving both amino and carboxylic acid groups)

Estimate Ni and Al present in solution.
Ni by using Dimethyl glyoxime by gravimetric method
Al by usng oxine (8 - hydroxy quinoline)  gravimetric method
Refer book or class notes for the estimation in Coordination Compounds.

How is alanine prepared?
Alanine can be prepared by Strecker synthesis.
 Acetaaldehyde, ammonia, and hydrogen cyanide combined to form alpha amino nitrile which after hydrolysis give alanine.
Alanine react with LiAlH4 to form amino alcohol.(Refer reactions characteristic of carboxylic acid group)
Alanine react with HNO2 to form hydroxy acids and Nitrogen gas(Refer reactions characteristic of amino group.

Ether,chloroform and alcohol in a vessel.How many phases and components are present?
The three together make ONE phase and THREE components.

What  are Secondary Standard Substances? Give examples.
A secondary standard is a standard that is prepared in the laboratory for a specific analysis.
It is usually standardized against a primary standard.
  For example, making a primary standard solution of Na2CO3and then titrating that to find the accurate concentration of HCl will make the HCl solution secondary standard.

1.What are primary standard substances? Give examples.
A primary standard is a reagent that is extremely pure, stable, has no waters of hydration and has a high molecular weight .eg Sodium Carbonate, Sodium Oxalate, Potassium Dichromate
2.Mention the application of EDTA
To determine the hardness of water
To bind metal ions in chelation therapy
For treating mercury and lead poisoning
To remove excess iron from the body

1.Explain the biological role of chlorophyll

Chlorophyll acts as photosensitizer. Transfers energy to carbon di oxide and water molecule and helps in photosynthesis.

2.Define standard hydrogen electrode. What is its potential?

SHE is the universal reference for reporting relative half-cell potentials.The value of standard electrode potential is zero.

3. What is the application of Henderson Equation

It is used for estimating the pH of a buffer solution and to calculate the isoelectric point of proteins. 

The following is the answer for a two mark question from university exam question paper
What is the molarity of 1N Sulphuric acid solution?
Normality = 2 x molarity
 1 N / 2  = molarity
molarity is 0.5 M

Emergency and Utility Services Contact Details

Emergency Services

Service	Phone  Numbers
Police	100
Traffic Police	103
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Fire Control	101
Ambulance of Fire Services Dept.	102
Child Line	1098
Women Help Line	1091
Lions Blood Bank	28415959
Apollo Ambulance	1066
St. Johns Ambulance Association	28194630
Trauma Care Consortium	28150700
Government General Hospital	25305000
Government Kilpauk Hospital	28364951
Government Royapettah Hospital	28483051
Government Stanley Hospital	25281347
Govt. Hospital for Women & Children	28191982
Govt. Kasturba Hospital for Women	28545449
Institute of Child Health & Hospital	28191135
Child Trust Hospital	42001800
Voluntary Health Service	22541972
Chennai Corporation Complaints	1913
Railways Reservation Enquiry	132
Automated Reservation Query	139
Tourist Enquiry	1913
Tourism Office of Govt. of Tamil Nadu	25368538
Tourism Office of Govt. of India	28460285

How to put off kitchen fire....

Dear Students, The video is the demo of brown ring test for nitrate ion.