ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

Chemical composition of colemnite is:

• Ca₂B₆O₁₁.5H₂O A
• CaB₄O₇ .4 H₂O B
• Na₂B₇O₇. 4 H₂O C
• CaNaB₅O₉.8H₂O D

Which fills the space between needles in cement setting?

• Ca(OH)₂ A
• Al(OH)₃ B
• CaCO₃ C
• MgSO₄ D

In physical and chemical properties, transition elements show

• Similarities A
• Dissimilarities B
• Both of these C
• Somestimes similarities, sometimes dissimilarities D

An element that has a high ionization energy and tends to be chemically inactive would most likely to be

• an alkali metal A
• a transition element B
• a noble gas C
• a halogen D

Ammonium nitrate fertilizer is not used for which crop?

• Cotton A
• Wheat B
• Sugar-cane C
• Paddy rice D

• Moles per dm³ A
• Partial pressures B
• Number of moles C
• Mole fractions D

A standard hydrogen electrode is used as standard electrode of which electrode potential is arbitrarily taken as

• +1 A
• -1 B
• 0.1 C
• Zero D

Gypsom added in cement is

• 1% A
• 2% B
• 3% C
• 4% D

Acetamide and NaOBr/OH^-produce

• Ethanamine A
• Methanamide B
• CH₃CN C
• NH₃ D

Corrosion reaction are

• Spontaneous redox reaction A
• Non-spontaneous acid-base reactions B
• Spontaneous acid-base reactions C
• None of these D

Setting time of cement is controlled by adding

• Epsom A
• Gypsom B
• CaCO₃ C
• CaCl₂ D

Sodium should be stored in

• Air free from moisture A
• Air free form carbon dioxide B
• Under water C
• Under kerosene oil D

Down's cell is used to prepare

• Sodium carbonate A
• Sodium bicarbonate B
• Sodium metal C
• Sodium hydroxide D

Which of the following represents the correct electronic configuration of the outermost energy level of an element of zero (VIIA) group in the ground state?

• s²p² A
• s²p⁴ B
• s²p⁵ C
• s²p⁶ D

The nature of positive ray depend on:

• The nature of electrode. A
• The nature of discharge tube. B
• The nature of residual gas. C
• All of above. D

Gypsum is applied to the soil to provide calcium and

• Oxygen A
• Nitrogen B
• Phosphorous C
• Sulphur D

Calcium acetate when dry distilled gives

• Formaldehyde A
• Acetaldehyde B
• Acetone C
• Acetic anhydride D

A chemical reaction is in equilibrium when

• Formation of product is minimum A
• Reactants are completely transformed into products B
• Rates of forward and backward reactions are equal C
• Equal amounts of reactants and products are present D

β-β- dichloroethyle sulphide is commonly known as:

• Mustared gas A
• Laughing gas B
• Phosgene gas C
• Bio gas D

Which of the following is a noble gas:

• Ne. A
• Cl₂. B
• H₂. C
• N₂. D

Mixture of alcohol and water can be separated by

• Solvent extraction techniques A
• Crystallization B
• Precipitation and filtration C
• Fractional distillation D

All C - H bond lengths of benzene ring is

• 1.07A° A
• 1.09A° B
• 1.08A° C
• None D

Ionization energy does not increase?

• With small atomic radius of atom A
• If increase in no of electronic shells B
• By increase in proton no of atom C
• None of these D

Which of the following is strangest reducing agent.

• Cl- A
• K+ B
• Ar C
• Ca+2 D

CFCs destroy ozone layer. How many ozone molecule a chlorine free radical can destroy

• 10,000 A
• 20,000 B
• 100,000 C
• 50,000 D

A smuggler could not carry gold by chemically depositing iron on the gold surface since

• Gold is denser A
• Iron rusts B
• Gold has higher reduction potential then iron C
• Gold has lower reduction potential then iron D

Which of the following statements is not true?

• Isotopes with even atomic masses are comparatively abundant A
• Isotopes with even atomic masses are comparatively abundant B
• Isotopes with even atomic masses and even atomic numbers are comparatively abundant C
• Isotopes with even atomic masses and odd atomic number are comparatively abundant D

Rusting can be avoided by :

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

With increasing principle quantum number, the energy difference between adjacent energy levels in H atom

• Decreases A
• Increases B
• Remains constant C
• Decreases for low value of Z and increase for higher value of Z D

• 2, 2, 4-trimethylpentane A
• 2, 4, 4-trimethylpentane B
• 2, 4, 4-methyepentane C
• 2, 2, 4-methylpentane D