ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

NH₃, HCL, H₂O, HL are:

• Diatomic molecules

  A

• Poly-atomic molecules

  B

• Mono-atomic molecules

  C

• Hetero atomic molecules

  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

A molecule of haemoglobin is made up if nearly

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

Isotopes differ in

• properties which depend upon mass A
• arrangement of electrons in orbitals B
• chemical properties C
• the extent to which they may be affected in electric fields D

A species having positive or negative charge is called:

• Electron A
• Ion B
• Proton C
• Atom 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 volume occupied by 1.4 g of N₂ at S.T.P is

• 2.24 dm³ A
• 22.4 dm³ B
• 1.12 dm³ C
• 112 cm³ 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 an electron is added to a uni positive ion we get:

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

Which one of the following statements is not correct

• A molecule is the smallest particle of an element which can exist independently A
• He is a molecule of helium B
• S₈is a molecule of sulphur C
• O₃is a molecule of oxygen D

Which of the sub-atomic particles is not charged

• Electron A
• Proton B
• Neutron C
• All of them D

The atomic mass is measured in atomic mass unit (a.m.u.) which is equal to

• 1.661 x 10^{-27- Kg} A
• 1.661 x 10^-24Kg B
• 1.661 x 10^{-27- g} C
• 1.661 x 10^-24mg D

First atomic theory was put forward by an English school teacher:

• Maxewell A
• Newton B
• Sanger C
• John Dalton D

The number of isotopes of gold is

• 3 A
• 1 B
• 2 C
• 4 D

Metal tend to lose electrons, becoming:

• Metals

  A

• Positively charged

  B

• Negatively charged

  C

• (a)And (c)

  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

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

• Positrons

  A

• Photons

  B

• Ions

  C

• Electrons

  D

Ascorbic acid contains 40.92% carbon, 4.58%, hydrogen and 54.4% oxygen. The empirical formula is

• C₃H₄O₃ A
• C₂H₄O₃ B
• C₃H₅O₄ C
• C₂H₃O₁ D

Which one of the following step is not involved in determination of empirical formula

• Determination % of each element A
• Determination of gram atom of each element B
• Determination of isotopes of each element C
• Determination of atomic ratio of element D

A balloon contains 0.02 gram of H₂gas, it contains H₂molecules

• 6.02 x 10²³ A
• 3.01 x 10²² B
• 6.02 x 10²¹ C
• 3.01 x 10²¹ D

The number of atoms present in molecule determines its:

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

• 
  A
• 
  B
• 
  C
• 
  D

Benzene is stable to:

• Oxidation A
• Nitration B
• KMnO₄ C
• SULPHONATION 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

Isotopes differ in the

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

The atom of an element is

• The smallest particle A
• The fundamental particle B
• The independent particle C
• The charged particle D

Two different hydrocarbon each contain the same percentage by mass of hydrogen. It follows that they have the same

• Empirical formula A
• Number of atoms in a molecules B
• Number of isomers C
• Relative molecular mass D

The empirical formula of a compound is CH₂O. What may be the compound

• C₂H₅OH A
• C₆H₅OH B
• HCOOH C
• 
  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

Atoms can be evident by use of electron microscope, field ionization microscope and:

• x-rays A
• Video camera
  
  
  B
• Telescope C
• Compound microscope D