In polarography the substance to be analyzed undergoes electrolysis under the

influence of potential difference  result in generation of current in electrolytic cell.

Polarograph: An electrical apparatus used for supplying voltage for electrolysis of an

electrolyte is called polarograph – it consist of potentiometer, an electrolyte cell or

polarographic cell and galvanometer.

Polarographic wave –voltage relationship of  polarogram

  • initially very small gradual increases in current known as residual current (ir)
  • Residual current ((ir) is sum of the faradic current (if) and condenser current (ic)  i.e. ir = if  + ic
  • Current increases rapidly because more number of ions moves towards the electrode surface of DME from the solution carries current. At the half wave potential E1/2 à concentration of oxidized and reduced form of electrode surface is equal à this potential is the characteristic of the reducing substance.
  • Diffusion current (id) or limiting current (il) gives straight line in absence or presence of electrolyte used à depending upon the concentration of reducing substance.

Ilkovic equation  

id = 607 n D1/2 c m2/3 t1/6

id             =          diffusion current during life of drop (amperes)

607      =          constant generated from π, faraday constant and density of mercury

n          =          the number of electrons involved

D         =          the diffusion coefficient in cm2 s-1

Elementary Reactions and Mechanism:
Elementary reactions are steps of molecular events showing how reactions proceed. This type of description is a mechanism.

The mechanism for the reaction between CO and NO2 is proposed to be

Step 1   NO2 + NO2 –>   NO3 + NO   (an elementary reaction)
Step 2   NO3 + CO –>   NO2 + CO2   (an elementary reaction)

Add these two equations led to the overall reaction

NO2 + CO = NO + CO2     (overall reaction)

Molecularity of Elementary Reactions:
The total order of rate law in an elementary reaction is molecularity.
The rate law of elementary reaction is derived from the equation. The order is the number of reacting molecules because they must collide to react.

1. A molecule decomposes by itself is a unimolecular reaction (step);
2. Two molecules collide and react is a bimolecular reaction (step); &
3. Three molecules collide and react is a termolecular reaction (step).

O3 –>  O2 + O     rate = k [O3]

NO2 + NO2 –>   NO3 + NO    rate = k [NO2]2

Br + Br + Ar –>   Br2 + Ar*    rate = k [Br]2[Ar]


ALL INDIA COUNCIL FOR TECHNICAL EDUCATION (AICTE) has started conducting the computer based online National level GRADUATE PHARMACY APTITUDE TEST (GPAT). The notification is issued to announce the schedule for conducting computer based online GPAT for admission for academic year 2018-19.

The complete schedule as per the advertisement published by AICTE on the official website.

Registration Starts on 20 october 2017
Last Date for Online Registration 18 December 2017
Print out of Hall ticket First week of  Jan 2018
Computer Based Test Dates 20 Jan 2018
Test Timings -
Declaration of Result yet to be announced
Print out of Score Card After declaration of Result

Eligibility : Bachelor’s degree holders in Pharmacy (4 years after 10+2, including lateral entry candidates) and those who are in the final year of B. Pharmacy course are eligible for appearing in GPAT-2018 examination.

Registration:  online from 20 october, 2017 to 18 December, 2017 on website Choice of 3 cities for online examination in the order of preference. Allotment will be based on first come first served. Actual allotment however will be subject to availability of the slots in a particular city.

Test Fees:General and OBC Candidates: Rs. 1400 + Bank Charges as applicable.
SC / ST / PD + Ladies: Rs. 700 + Bank Charges as applicable.

Test Conducted in following Cities: 
Ahmadabad, Gurgaon,  Madurai, Rajkot, Allahabad, Guwahati, Mangalore,Ranchi, Amravati, Gwalior, Meerut, Shimla, Amritsar, Hyderabad, Mumbai, Surat, Aurangabad, Indore, Mysore, Thiruvananthpuram, Bangalore, Jabalpur, Nagpur, Tirupati, Bareilly, Jaipur, Nanded, Udaipur, Bhavnagar, Jammu, Nasik, Vadodara, Bhopal, Kanpur, Nellore, Varanasi, Bhubaneswar, Kochi, Noida, Vijayawada, Chandigarh, Kolhapur, Panaji, Visakhapatnam, Chennai, Kolkata, Patna, Warangal, Dehradun, Kozhikode, Pune, Delhi, Kurnool, Raipur, Gulbarga, Lucknow, Rajahmundry.

For detailed information please visit website

Test Series and Study Material: is a web portal provide whole study material and scheduled test series for GPAT 2018.

The Study material includes All subjects viz. Pharmaceutics, Pharmacology, Medicinal Chemistry, Pharmacognosy, Pharmaceutical analysis, Physical Pharmacy, Biopharmaceutics, Organic Chemistry, Pharmaceutical Jurisprudence, Dispensing Pharmacy, Cosmetics, Microbiology and Some important topics like Medicinal drug Synthesis, Metabolites, Basic rings, and Formula’s.

Test series 2018 includes subjectwise planed test and learning tool, various practice test and Pre-GPAT 2018 Examination.

For more details visit:

Best of Luck for GPAT 2018…….