ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

Bleaching powder is agent:

• Dehydrating A
• Oxidazing B
• reducing C
• all D

First of all, idea of groups and periods was introduced by:

• Al-Razi A
• Dobriener B
• Newland C
• Mendeleev D

An alcohol with molecular formula C_nH_2n+1OH has a chiral carbon atom but does not react with MnO^-₄/H⁺what is the least number of carbon atoms such an alcohol could possess

• 5 A
• 6 B
• 7 C
• 8 D

The self linking of carbon atoms is called

• Chelation A
• Isomerism B
• Catenation C
• None of the above D

Which phosphorus is the most poisonous?

• White A
• Red B
• Black C
• All D

The quantum number which describes the shape of the orbital is

• Principle quantum number A
• Spin quantum number B
• Azimathal quantum number C
• Magnetic quantum number D

Which class of compound is more reactive

• Alkane A
• Alkene B
• Alkyne C
• None D

Best medhod of preparation of alkyl halide from alcohals is by its reaction with:

• HX A
• SOCl₂ B
• Px₅ and PX₃ C
• All D

Which are metalloid?

• Nitrogen and phosphorous A
• Arsenic and phosphorous antimony B
• Phosphorous and arsenic C
• Antimony and bismuth D

When 0.1 g of magnesium is treated with an excess of hydrochloric acid, what volume of gas at room temperature and pressure will be produced

• 10 cm³ A
• 25 cm³ B
• 48 cm³ C
• 100 cm³ D

Alkene general formula :

• C_nH_2n+2 A
• C_nH_2n B
• C_nH_2n-2 C
• C_nH_2n+1 D

Which of the following possesses the highest melting point?

• Chlorobenzene A
• 0-Dichlorobenzene B
• m-Dichlorobenzene C
• p-Dichlorobenzene D

A compound possessingα-hydrogen atom, in the presence of dilute alkali formsβ-hydroxy aldehyde. This product on heating with dilute acid forms an unsaturated crotonaldehyde. The compound is

• CH₃CHO A
• CH₃CH₂CHO B
• CH₂= CH - CHO C
• HC = C - CHO D

The tip of the funnel should touch the side of the beaker in order to avoid

• Splashing A
• Leakage B
• Mixing C
• Contamination D

The formula of calcium superphosphate is

• CaHPO₄ A
• CaH₂PO₄ B
• Ca(H₂PO₄)₂ C
• None of these D

Azimuthal quantum number of last electron of ₁₁Na is

• 1 A
• 2 B
• 3 C
• 0 D

The alkaline earth elements have in their s-orbital

• One electron A
• Two electron B
• No electron C
• Three electron D

In exothermic reaction decrease in potential energy of the products will result in

• Decreases in kinetic energy of the particles A
• Increases in kinetic energy of the particles B
• No change in kinetic energy C
• Decreases in activation energy D

Best way to prevent rusting of iron is by

• Making iron cathode A
• Putting it in saline water B
• Both of these C
• None of these D

Which is an inert gas?

• Nitrogen A
• Oxygen B
• Hydrogen C
• CO D

The reduction potential to copper electrode is +0.34 V and that of Zn electrode is -0.76 V. when these two are coupled the e.m.f. of the cell is

• -0.42 V A
• +0.42 B
• -1.10 V C
• +1.10 V D

Which of the following method is most appropriate for the manufacture of methane?

• By reduction of CH2CL2 A
• Wurtz reaction B
• Liquification of natural gas C
• None of these D

Compounds X, Y and Z, all react with PCI₅to release hydrogen chloride, but only one of them reacts eith 2,4-dinitrophenylhydrazine reagent. Which one of the following combinations could be X, Y and Z

• 
  A
• 
  B
• 
  C
• 
  D

Precipitation will occur until the ionic product becomes

• Equal to K_sp A
• Lesser than K_sp B
• Greater than K_sp C
• None of these D

Camphor is often used in molecular mass determination because

• It is solvent for organic substances A
• It is readily available B
• It has a very high cryoscopic constant C
• It is volatile D

]Which of the following is a pseudo solid?

• Atoms of He is gaseous stat at high temperate. A
• Molecules of water in liquid state. B
• Molecules of solid l₂ C
• Molecular of hydrochloric acid gas D

Which factor is helping to reduce the environmental pollution

• Rapid growth of population A
• Urbanization B
• Industrialization C
• Increase of plantation D

• Excitantion of an electron from 2s to 2p-orbital A
• Transfer of three electrons from B to the other atoms B
• Excitation of two electrons form 2s orbital to 2p orbital C
• Formation of molecular ion D

A compound having empirical formula C₃H₃O and its molecular mass is 110.02. Its molecular formula is

• C₃H₃O A
• C₆H₆O₂ B
• C₉H₉O₃ C
• C₃H₆O₂ D

Alkyle magnesium halides are known as

• Simon-smith reagent A
• Tollen's reagent B
• Grignard's reagent C
• Barford's reagent D