Download PDF Chemistry Past Papers To Get 100% Marks in All Punjab 2023 Exams
Are you finding 2nd Year (12th Class) Chemistry Past Papers? 12th Class Chemistry is subject of atomic compositions and long chemical equations. Lahore board Fsc part 2 students generally have trouble passing the course mainly because most of the syllabus is based on organic chemistry. Chemistry “is the branch of chemistry which revolves around carbon-containing compounds”. Students are often unable to retain endless formulas and long equations in their brains. You can download PDF files of past 2nd year chemistry jobs for Lahore board from below.
(i) Define periodic table. How many group and periods are present in it?
(ii) Define (i) Mendeleev’s periodic law
(ii) Different between alkali metals and alkaline earth metals.
Give one example in each case.
(iv) Write down the formulas of the following minerals:
(v) Write down four uses of borax.
(vi) Define the chemical garden.
(vii) Write down two similarities and two dissimilarities of oxygen and Sulphur.
(viii) Write four differences of nitrogen from its family.
(ix) Why does aqua Regia dissolve gold and platinum?
(x) Write down four essential qualities of good fertilizer.
Rawalpindi Board Chemistry 12th Past Paper 2019
(i) Define organic chemistry. What is vital force theory?
(ii) Write down structural formulas of the following:
(c) 3-Ethyl pentane
(d) 4-Dimethyl pentane
(iii) Write down four uses of methane.
(iv) Define aromatic hydrocarbons. How they are classified?
(v) What happens when
(a) Benzene is heated with conc. H 50, at 250°C.
(b) Chlorine is passed through benzene in sunlight.
(vi) Define alkyl halides. What are primary alkyl halides? Give one example.
(vii) Define Grignard reagent. Give one example.
(viii) How ethanal is prepared from molasses? Write chemical reaction as well.
(a) Absolute alcohol
(b) Methylated spirit
(c) Rectified spirit
(d) Denaturing of alcohol
DG Khan Board 12th Class Chemistry Past Papers 2019
Write short answers to any SIX (6) questions:
(1) What is iodized salt?
(ii) Why iodine has metallic luster?
(iii) Give four applications of noble gases.
(iv) What are interstitial compounds?
(v) How will you convert ethanol into lactic acid?
(vi) How will you distinguish between benzaldehyde and ethanal ?
Give respective chemical reactions.
(vii) How is polyvinyl chloride prepared and give uses?
(viii) How is nylon – 6, 6 prepared?
Bahawalpur Board Past Paper Chemistry 2019
(a) Describe the role of lime in industries.
(b) What are the hydrides, describe different types of hydrides?
(a) Define corrosion. Explain the electrochemical theory of corrosion.
(ix) What is the function of RNA and DNA?
(a) What is orbital hybridization? Explain spa hybridization with an example.
(b) Discuss atomic orbital treatment to explain the structure of benzene.
(a) How can the following conversions be carried out:
(1) (i)Ethane → Methane (ii) Methane → Ethane
(b) How Will can ethers be prepared by the Williamsons method and from Ag2O?