ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

• 154 pm A
• 133 pm B
• 120 pm C
• 150 pm D

Transition elements are called so because:

• Form interstital sompounds A
• have high m.p B
• In between 's' and' 'p' block elements C
• All of these D

The fibre which is made from vinylidine chloride polymer is called

• Rayon fibre A
• Azlon fibre B
• Acetate fibre C
• Saran fibre D

What happens when reaction is at equilibrium and more reactant is added :

• Forward reaction rate is increased. A
• Forward reaction rate is decreased. B
• Backward reaction rate is increased. C
• Equilibrium remains unchanged. D

The bond angles in methane CH₄are equal to

• 109.5° A
• 107.5° B
• 104.5° C
• 120° D

n + l value for 4f will

• 2 A
• 5 B
• 7 C
• 9 D

Which of the following elements is not present abundantly in earth's crust?

• Silicon A
• Aluminium B
• Sodium C
• Oxygen D

Polycyolic aromatic hydrocarbons are taught to be

• Disinfectant A
• Carcinogenic B
• Helpful C
• Reactive D

Alkynes are colourless & odouless except

• Acetylene A
• Propyne B
• Butyne C
• Pentyne D

When alkyl halide is heated with aqueous solution of ammonia at 100°C the major product is

• Primary amine A
• Secondary amine B
• Tertiary amine C
• Mixture of amines and salt D

In a group on going downward, polarizability generally

• Decreases A
• Increases B
• Remains constant C
• Negligible D

An electric current is passed through silver nitrate solution using silver electrodes.10.79 g of silver was found to be deposited on the cathode if the same amount of electricity is passed through copper sulphate solution using copper electrodes, the weight of copper deposited on the cathode is

• 6.4 g A
• 2.3 g B
• 128.8 g C
• 3.2 g D

Sodium belongs to block of periodic table:

• S-Block A
• p- block B
• d- block C
• f- bloci D

Of the following four reactions, formic acid and acetic acid differ in which respect?

• Replacement of hydrogen by sodium A
• Formation of ester with alcohol B
• Reduction of Fehling solution C
• Blue litmus reaction D

BiCl₃on hydrolysis forms a white precipitate of

• Bismuthio acid A
• Bismuth oxychloride B
• Bismuth pentachloride C
• Bismuth hydroxide D

During nitration of benzene, the active nitrating agent is:

• NO₃^-1 A
• NO₂₊ B
• NO₂^-1 C
• HNO₃ D

Value of rate constant k is specific for a reaction, and varies from reaction to reaction. The value of k of a reaction changes with

• Time A
• Temperature B
• Concentration of reactants C
• Order of reaction D

Which of the following has highest oxidation potential

• Be A
• Li B
• Na C
• Ca D

Kolb's method is not useful for the production of

• Methane A
• Ethane B
• Propane C
• Butane D

A filtration process could be very time consuming if it were not aided by a gentle suction which is developed:

• If the paper covers the funnel up to its circumstances A
• If the paper has got small sized pores in B
• If the stem of funnel is large so that it dips in to filtrate C
• If the paper fits tightly. D

Polyester resins have special use in:

• Clothing A
• Paints B
• Emulsion C
• Floor covering D

According to modern theory of chemical bonding atoms form bonds as it leads to a:

• First decrease then increase in energy. A
• Decrease in energy. B
• No energy change. C
• Increase in energy. D

White phosphorus is

• A mono atomic gas A
• P₄, a tetrahedral solid B
• P₈, a crown C
• A linear diatomic molecule D

Calcium carbonate contains oxygen in it

• 48% A
• 50% B
• 53% C
• 60% D

Cotton has cellulose in it:

• 96% A
• 97% B
• 98% C
• 99% D

Micro-nutrients are required in quantity ranging from

• 4g-40g A
• 6g-200g B
• 6Kg-200Kg C
• 4Kg-40Kg D

Negatively charged particle nature of cathode rays was first demonstrated in 1895 by:

• Millikan. A
• J. Perrin. B
• Hittrof C
• J.J. Thomson. D

The acid which has a peroxy linkage is

• Sulphurous acid A
• Pyrosulphuric acid B
• Dithionic acid C
• Caro's acid D

18 g glucose is dissolved in 90 g of water. The relative lowering vapor pressure is equal to :

• 1/5 A
• 5.1 B
• 1/51 C
• 6 D

Which of the following may affect the rate constant (k) fro a reaction :

• Change in concentration. A
• Change in pressure. B
• Change in pH. C
• Change in temperature. D