ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

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

A limiting reactant is one which according to the stoichiometric equation

• Has excess mass A
• Has least mass B
• Has excess number of moles C
• Has least number of moles D

The phenomenon of isotropy was first discovered by

• Soddy A
• Rutherford B
• Bohr C
• Dalton 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

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

The atom of an element is

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

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 diameter of atoms is of the order:

• 2* 10^-5m A

• 2* 10^-10 m

  B
• 2* 10^-2m C
• 2* 10^-3m 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

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

• Positrons

  A

• Photons

  B

• Ions

  C

• Electrons

  D

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

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

CL₂, N₂ and O_{2 are:}

• Diatomic molecules

  A

• Hetero atomic molecules

  B

• Poly-atomic molecules

  C
• Mono-atomic molecules D

Each molecule of haemoglobin is 68000 times heavier than one atom of

• C A
• H B
• N C
• O D

• 300 cm³ A
• 200 cm³ B
• 150 cm³ C
• 100 cm³ D

Which statement about an atom is true ?

• The number of neutrons is not equal to number of electrons A
• Mass number is less than atomic number B
• All the elements have only one mass number C
• Mass number can be equal to atomic number 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

If four moles of sulpur dioxide are oxidised to sulphur trioxide, how many moles of oxygen molecules are required

• 0.5 A
• 1.0 B
• 1.5 C
• 2.0 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

Formation of a cation is:

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

0.5 mole of CH4and 0.5 mole of SO2gases have equal

• Volume A
• Mass in grams B
• Total number of atoms C
• Number of molecules D

CO+ is an example of

• Stable molecule A
• Anionic molecule ion B
• Cationic molecular ion C
• Free radical D

The percentage of H is the highest in

• CH₄ A
• NH₃ B
• H₂SO₄ C
• C₆H₁₂O₆ D

A species having positive or negative charge is called:

• Electron A
• Ion B
• Proton C
• Atom 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

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

• 99.2% A
• 99.5% B
• 90.5% C
• 96.2% 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

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

NH₃, HCL, H₂O, HL are:

• Diatomic molecules

  A

• Poly-atomic molecules

  B

• Mono-atomic molecules

  C

• Hetero atomic molecules

  D