ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

The relative atomic mass of chlorine is 35.5. What is the mass of 2 mol of chlorine gas

• 142 g A
• 71 g B
• 35.5 g C
• 18.75 g D

Benzene is stable to:

• Oxidation A
• Nitration B
• KMnO₄ C
• SULPHONATION D

An ion bearing positive charge is called:

• Cation A
• Positron B
• Anion C
• None of above D

X-ray work has shown that the diameters of atom are of the order of

• 8 x 10^-10m A
• 2 x 10^-10m B
• 8 x 10^-8m C
• 2 x 10^-8 m 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

A compound contains one atom of oxygen and % of O 34.78, then molecular mass of compound is

• 46 A
• 78 B
• 110 C
• 180 D

0.5 mole of CH₄and 0.5 mole of SO₂gases have equal

• Volume A
• Mass is gram B
• Total number of atoms C
• Number of molecules D

Mass spectrometer measures the

• Exact mass of an element A
• Average mass of an element B
• The number of elements present in a molecule C
• m/e value of a positive ion D

One mole of ethanol and one mole of ethane have an equal

• Mass A
• Number of atoms B
• Number of electrons C
• Number of molecules D

The percentage of H is the highest in

• CH₄ A
• NH₃ B
• H₂SO₄ C
• C₆H₁₂O₆ D

The relative abundance of Pb isotopes is 1.5% Pb²⁰⁴, 23.6% Pb²⁰⁶, 22.6% Pb²⁰⁷, 52.3% Pb²⁰⁸The relative atomic mass of Pb is

• 207.94 A
• 208.24 B
• 206.94 C
• 207.24 D

When an electron is added to a uni positive ion we get:

• Cation A
• Molecule B
• Neutral atom C
• Anion D

The isotopes of an element

• Possess same mass number A
• Possess same number of protons B
• Do not possess same chemical properties C
• May or may not possess same chemical properties D

A molecular ion is formed by

• Passing a high energy electron beam through gaseous molecule A
• Dissolving a salt i dilute acid B
• Passing electric current through molten salt C
• Passing electricity through aqueous solutions 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

• 0 dm³ A
• 3 dm³ B
• 2 dm³ C
• 3 dm³ D

Which has greater number of moles

• 0.1 g sodium A
• 6.02 x 10²⁰atoms of magnesium B
• 20 cm³0.1mole per dm³of NaOH C
• 12.2 dm³of nitrogen at standard
  [A_rNa = 23, Mg = 24, O = 16]
  D

The wave length of visible light is 500 nm. In S.I. unit this value is

• 5 x 10^-8m A
• 5 x 10^-9m B
• 500 x 10^-7m C
• 500 x 10^-9m D

Which of the following compounds contains the highest percentage by mass of nitrogen?

• Ammonia, NH₃ A
• Ammonium carbamate, NH₂CO₂NH₄ B
• Ammonium carbonate, (NH₄)₂CO₃ C
• Hydrazine, N₂H₄ D

• 32 g A
• 3.2 g B
• 5.6 g C
• 9.6 g D

Molecules of High molecular weight usually greater than 10,000 are called:

• Macro molecules A
• Mega molecules B
• Poly molecules C
• Gega molecules D

The number of isotopes of gold is

• 3 A
• 1 B
• 2 C
• 4 D

The number of moles of CO2which contain 8.0 g of oxygen

• 0.25 A
• 0.50 B
• 1.0 C
• 1.50 D

Which one of the following compounds does not have the empirical formula CH₂O?

• Ethanoic acid, CH₃CO₂H A
• Ethanol, CH₃CH₂OH B
• Glucose, C₆H₁₂O₆ C
• Methanal, HCHO D

Isotopes of an element differ in

• Number of protons A
• Number of electrons B
• Number of neutrons C
• Number of electrons and protons D

A beaker contains 9 grams of water. The number of H atoms is

• 6.02 x 10²³ A
• 3.01 x 10²³ B
• 6.02 x 10²⁴ C
• 3.01 x 10²⁴ D

He Ar and Ne are:

• Mono-atomic molecules A

• Hetero atomic molecules

  B

• Poly-atomic molecules

  C

• Diatomic molecules

  D

Determination of atomic masses and invention of system of writing symbols was made by:

• J. Berzelius A
• Democritus B
• Dalton C
• None of above D

The number of atoms present in molecule determines its:

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

The mass of Al₂S₃formed when 20 grams Al reacts completely with S is

• 60 g A
• 50 g B
• 50.55 g C
• 55.55 g D