CBSE class 9 Science Quiz | CBSE class 9 Science Multiple Choice Questions(MCQs) with Answers

Questions
61 Which of the following is a heterogeneous mixture?
A lime water
B sugar dissolved in water
C air
D brass

Answer: lime water
62 Which of the following is NOT true about colloids?
A A colloid is a homogeneous solution.
B Colloidal particles exhibit electrophoresis.
C Particles in a colloid can pass through filter paper.
D Colloidal particles exhibit Brownian motion.

Answer: A colloid is a homogeneous solution.
63 Which of the following will have maximum mass?
A 0.1 mole of NH3
B 1022 atoms of Carbon
C 1022 molecules of CO2
D 1 gm of Fe

Answer: 0.1 mole of NH3
64 Which of the following is not correctly matched?
A Copper - Co
B Gold - Au
C Calcium - Ca
D Silver - Ag

Answer: Copper - Co
65 A sample of ammonia molecule irrespective of source, contains 82.35% of Nitrogen and 17.65% of Hydrogen by mass. This data supports:
A Law of Definite Proportions
B Avagadro's Law
C Law of Conservation of Mass
D Las of Multiple Proportions

Answer: Law of Definite Proportions
66 The percentage of Hydrogen in H2O molecule is
A 11.11
B 88.89
C 5.55
D 44.45

Answer: 11.11
67 Formula for Aluminium Oxide is:
A Al2O3
B Al3O2
C AlO
D none of these

Answer: Al2O3
68 1 u or 1 amu means
A Mass of Hydrogen molecule
B Mass of C-12 atom
C 1/12th mass of C-12 atoms
D Mass of O-16 atom

Answer: 1/12th mass of C-12 atoms
69 The number of moles for 52g of He is: (Atomic Mass of He: 4u)
A 6.022 × 1023
B 13
C 52
D 1

Answer: 13
70 The number value 6.022 × 1023 is also called
A Avagadro's number
B Mass Number
C Dalton Number
D Atomic Number

Answer: Avagadro's number
71 Who introduced the term 'mole' in chemistry?
A Wilhelm Ostwald
B A Lavosier
C John Dalton
D Amedeo Avagadro

Answer: Wilhelm Ostwald
72 Law of Definite Proportions was proposed by:
A Wilhelm Ostwald
B John Dalton
C Joseph Proust
D None of these

Answer: Joseph Proust
73 Who laid the foundation of laws of Chemical Combination:
A Lavoisier
B Proust
C Democritus
D Dalton

Answer: Lavoisier
74 Name the Indian Philospher who "the smallest indivisible particles of matter" as Parmanu
A Democritus
B Pakudha Katyayama
C Maharishi Kanad
D Aryabhatt

Answer: Maharishi Kanad
75 The maximum number of electrons that can be accommodated in M shell is:
A 18
B 19
C 5
D 7

Answer: 18
76 Which one of the following will have the maximum charge/mass ratio?
A α-particle
B neutron
C proton
D electron

Answer: electron
77 The number of electrons in the outermost shell in the atom of an inert element is
A 8
B 2
C 0
D 1

Answer: 8
78 The electronic configuration of an atom is 2,8,3. The number of valence electrons in the atom is
A 3
B 8
C 10
D 13

Answer: 3
79 If Z represents the atomic number and A represents mass number, then the number of neutrons in an atom can be computed as
A A – Z
B Z – A
C A + Z
D Z

Answer: A – Z
80 Protium, Deutrium and Tritium are isotopes of ____________.
A Hydrogen
B Helium
C Rhodium
D Sodium

Answer: Hydrogen
junior administrative assistant jaa test series