ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

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

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

Which of the following statement is correct for a chemical reaction to occur molecules of substances must

• Collide with each other A
• Collide with energy more than activation energy B
• Collide with energy less than activation energy C
• Collide with high frequency D

A molecule of haemoglobin is made up if nearly

• 10,000 atoms A
• 50,000 atoms B
• 2500 atoms C
• 1500 atoms 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

Atoms and molecules can either gain or lose electrons, forming charge particles called:

• Positrons

  A

• Photons

  B

• Ions

  C

• Electrons

  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

The quantitative relationship between the substances according to balanced equation describes

• Reversible reactions A
• Stoichiometry B
• Limiting reacting C
• Percentage composition D

Objects of the size of an atom can be observed in

• An electron microscope A
• An x-ray spectrum B
• Atomic absorption spectrum C
• A visible spectrum D

Matter is defined as any thing which occupies space and:

• Molecules A
• Mass B
• Compound C
• Molecules D

How many moles of hydrogen atoms does 3.2 g of methane, CH₄, contain?

• 0.02 A
• 0.2 B
• 0.4 C
• 0.8 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

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

The mass of one mole of proton is

• 1.008 g A
• 0.184 g B
• 1.673 g C
• 1.008 mg D

3.01 x 10²²Ag⁺ions is present in

• 85 grams AgNO₃ A
• 0.85 g AgNO₃ B
• 8.5 g AgNO₃ C
• 18.5 g AgNO₃ D

• 84.84 % A
• 89.89% B
• 81.81% C
• 90.90% D

What is the maximum mass of aluminium which can be obtained from 240g of aluminium oxide Al₂O₃?

• 26 g A
• 127 g B
• 51 g C
• 108 g D

How many moles of oxygen, O₂are needed for the complete combustion of two moles of butane C₄H₁₀?

• 2 A
• 8 B
• 10 C
• 13 D

Formation of a cation is:

• Exothermic process A
• Non-endothermic process B
• Endothermic process C
• None of above D

Where energy is released during a reaction it is

• Exothermic reaction A
• Endothermic reaction B
• A free radical reaction C
• A bond breaking reaction D

One mole of SO₂contains

• 6.02 x 10²³atoms of oxygen A
• 18.1 x 10²³, molecules of SO₂ B
• 6.02 x 10²³ atoms of sulphur C
• 4 gram atoms of SO₂ 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

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

One of the following statements is incorrect

• Actual yeild is always less than the theoretical yield A
• The formula of a compound is not definite B
• Law of conservation of mass is applied in stoictiometry C
• Boyles law is applied in stoichiometry D

A compound contains 75% carbon and 25% hydrogen, by mass. What is the molecular formula of the compound/

• C₃H₈ A
• CH₄ B
• C₂H₄ C
• C₂H₆ D

• 8 g A
• 16 g B
• 32 g C
• 24 g D

The phenomenon of isotropy was first discovered by

• Soddy A
• Rutherford B
• Bohr C
• Dalton D

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

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

1.12 dm³of N₂gas at S.T.P. has mass of N₂gas

• 2.8 g A
• 2.4 g B
• 1.4 g C
• 14 g D

The number of isotopes of gold is

• 3 A
• 1 B
• 2 C
• 4 D