ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

The empirical formula of a liquid compound is known to be C₂H₄O. What other information is needed to work out its molecular formula?

• The percentage composition of the compound A
• The relative molecular mass of the compound B
• The density of the compound C
• The volume occupied by one mole of the compound D

• -110.7 KJ/mole A
• +110.7 KH mole^-1 B
• 676.7 KJ mole^-1 C
• +393.7 KH mole^-1 D

Allotropic forms of sulpher are

• Two A
• Three B
• Four C
• Five D

Poly hydroxyl compounds of aldehyde ketones are:

• Carbohydrates A
• Protiens B
• Fats C
• Lipids D

Ionic solids are characterized by :

• Low meeting points A
• Good conductivity in solid state B
• High vapor pressure C
• Solubility in polar solvents D

The other name of cross linked polymers is

• Linear polymer A
• Branched polymer B
• Inter connected polymers C
• None of these D

• Acidified AgNO_3(aq) A
• Fehling's solution B
• Na C
• Na₂XO_3(aq) D

In thermal decomposition of N₂O the half life period for two different initial concentrations of N₂O are

(i) 255 second for initial N₂O 290 mm Hg

(ii) 212 second for initial N₂O 360 mm Hg then it is

• Zero order A
• First order B
• Second order C
• Third order D

According to the SI-system heat contents are measured in units of

• Calorie A
• Joules B
• Ergs C
• Watts D

Rusting can be avoided by :

• Making alloys A
• Tin or Zinc plating B
• Use of enamel C
• All of these D

Chlorin heptoxide reacts with water to form:

• Hypochlorous acid A
• Chloric acid B
• Perchloric acid C
• Chlorine and oxygen D

B-atom in BF₃has

• sp³hybridization A
• sp²hybridization B
• sp hybridization C
• no hybridization D

Dehydrohalogenation of alkyl halides give

• Alkanes A
• Alkenes B
• Alkynes C
• Alkdehyde D

Main cause of reducing map is:

• Combustion of coal A
• NO and NO₂ B
• Un-Burnt Hydrocarbons C
• All of these D

Which of the following statements is true about Galvanic cell

• Anode is negatively charged A
• Reduction occurs at anode B
• Cathode is positively charge C
• Reduction occurs at cathode D

The amount of products obtained from the balanced chemical equation is regarded as

• Theoretical yield A
• Actual yield B
• % yield C
• Experimental yield D

NO₂ forms acidic solution

• Red A
• Blue B
• Green C
• Brown D

Lactic acid on oxidation by alkaline potassium permanganate gives

• Tartaric acid A
• Pyruvic acid B
• Cinnamic acid C
• Propionic acid D

A compound containing carboxyl group in them are called:

• Ketone A
• Ether B
• Carboxylic acids C
• Polycarboxylic acid D

Which of the following is acidic?

• SO₃ A
• N₂O B
• BeO C
• HgO D

• There is no change in temperature A
• No change in volume B
• Heat is absorbed C
• Heat is released D

The colour of transition metal complexes is due to:

• d-d transitions of electorns A
• Paramagnetic nature of transition B
• Ionization C
• Loss of s-electrons D

The number of atoms present in molecule determines its:

• Molecularity A
• Atomicity B
• Basicity C
• Acidity D

The change in heat energy of a chemical reaction at constant temperature and pressure is called

• entahlpy change A
• heat of sublimation B
• bond energy C
• internal energy change D

Among O, C, F, Cl, Br, the correct order of increasing radii is

• F O C Cl Br A
• F C O Cl Br B
• F Cl Br O C C
• C O F Cl Br D

Hydrocarbans, SO₂, CO, NH₃, nitrogen oxides and compounds of fluorine are called

• Primary pollutant A
• Secondary pollutant B
• Tertiary pollutant C
• None of these D

The weight of pure NaOH required to prepare 250 cm³of 0.1 N solution is

• 4 g A
• 1 g B
• 2 g C
• 5 g D

Gradation in properties in the periods of periodic tables are due to change in

• Atomic weight A
• The number of electrons B
• Number of protons C
• Electronic configuration D

K_spvalue for PbSO₄= 1.8 x 10^-8mole²dm^-6. The maximum concentration of Pb⁺⁺ions is

• 1.34 x 10^-4mole dm^-3 A
• 1.8 x 10^-4 B
• 3.6 x 10^-16mole dm^-3 C
• 1.0 x 10^-8mole dm^-3 D

Which of the following hydrides ionic in nature

• NaH A
• CH4 B
• NH4 C
• H2S D