CHEMISTRY GENERAL MCQS SST/ SUBJECT SPECAILIST
What is a mixture of Potassium Nitrate Powdered Charcoal and Sulphur called?
A. Pain
B. Glass
C. Gun Powder
D. Cement
Diameter of an atom is in the order of________________?
A. 0.2m
B. 0.2mm
C. 0.2nm
D. 0.2pm
Mass spectrometer is used to determine Mass number of isotopes and__________?
A. Atomic number
B. Relative abundance
C. Electronic configuration
D. All of the above
The number of peaks obtained in mass spectrometry shows__________?
A. Relative abundance
B. Average mass of element
C. Number of isotopes
D. Relative isotopic mass
Empirical formula of chloroform is___________?
A. CH2 C12
B. CH3C1
C. CC14
D. CHCL3
Molecular mass of water (18g) means___________?
A. 1-mole molecules of water
B. 1-gram molecule of water
C. 3-gram atoms
D. all
Which of the following statements about isotopes is correct?
A. Isotopes with odd atomic number are abundant
B. Isotopes with odd atomic number and even mass number are abundant
C. Isotopes with even atomic number and even mass number are abundant
D. Isotopes with even atomic number and odd mass no are abundant
One mole of CO2 contains.
A. 6.022 x 1023 atoms of oxygen
B. 22-gram electrons
C. 6.022 x 1023 atoms of carbon
D. both B. & C.
The number of isotopes of elements with even mass number and even atomic number are ________________?
A. 280
B. 300
C. 154
D. 54
Which of the following terms is not used for ionic compound?
A. formula unit
B. empirical formula
C. molecular formula
D. formula mass
moles of each aluminum and oxygen react with each other to produce aluminum oxide. The amount of product formed is______________________?
A. 0.18 mole
B. 0.27 mole
C. 0.24 mole
D. 0.09 mole
Which one of the following has the maximum number of isotopes?
A. oxygen
B. carbon
C. tin
D. chlorine
The volume occupied by 2.8 g of N2 at STP______________?
A. 2.24 dm3
B. 22.4 dm3
C. 1.12 dm3
D. 112 dm3
The number of moles of CO2 which contains 16 g of oxygen is_________?
A. 0.25
B. 0.5
C. 0.75
D. 1
How many isotopes have odd atomic number ?
A. 154
B. 280
C. 86
D. 300
Percentage of calcium in calcium carbonate is_________?
A. 80%
B. 30%
C. 40%
D. 20%
Mostly elements have fractional atomic masses because of______________?
A. Mass of an atom itself is in fraction
B. Atomic masses are average masses of isobars
C. Atmoic masses are average masses of isotopes proportional to their relative abundance
D. Atmoic masses are average masses of isotopes
Which of the following is not a macromolecule ?
A. sand
B. haemoglobin
C. diamond
D. maltose
Isotopes of the same elements has____________?
A. different number of protons
B. same number of neutrons
C. different number of neutrons
D. same mass number (nucleon number)
When cationic molecular ions are allowed to pass through strong magnetic field in mass spectrometer which of the following ions is fallen_____________?
A. lighter
B. intermediate
C. heavier
D. are collected at same time
For which of the following compounds the term empirical formula cannot be applied?
A. Nalco
B. H2O
C. CCI4
D. It can be applied to all mentioned above
The properties of an element mostly corresponds to that isotope which has greater__________?
A. Mass number
B. Atomic mass
C. Relative abundance
D. all of the above
1 a.m.u =__________________?
A. 1.6 x 10-27 kg
B. 1.6 x 10-24 kg
C. 1.6 x 10-26 kg
D. 1.6 x 10-28 kg
Which of the following are isoelectronic species?
A. H+ H H-
B. Li+ Na+ K+
C. C1- Br- I
D. F- Ne Na+
Molecular ions are formed by passing______________________?
A. High energy electron beam
B.? – Particle
C. X-rays
D. All of the above
Which one is true about isotope?
A. Same number of neutrons
B. Same mass number
C. Same physical properties
D. same chemical properties
Which of the following ion formation is always exothermic?
A. Unit-negative
B. Unit-positive
C. Di-negative
D. Di-positive
The sample of isotopes of an element, which needs not to be vaporized in the vaporization chamer_________________?
A. Gas
B. Liquid
C. Volatile solid
D. All
Avogadro’s number may represent_________________?
A. volume of particles
B. number of particles
C. mass of particles
D. All of the above
Size of molecule depends upon________________?
A. Atomicity
B. Shape of molecule
C. Both A and B
D. Difficult to predict
Which of the following terms is used for the mass of chlorine 35.5 ?
A. relative atomic mass
B. mass number
C. atomic weight
D. relative isotopic mass
Which one of the following is not the mono isotopic element ?
A. arsenic
B. uranium
C. iodine
D. nickel
The mass of decimole of electrons (NA) is________?
A. 1.008 mg
B. 0.184 mg
C. 0.054 mg
D. 5.4 mg
Which of the following statements is wrong about isotopes?
A. they possess different mass number
B. they possess different physical properties
C. they possess same chemical properties
D. they possess different position in the periodic table
Qualitative analysis is carried out for _________________?
A. identification of elements
B. estimation of amounts of elements
C. molar ration of elements
D. molar volume of elements
Combustion analysis is performed to determine___________?
A. Empirical formula
B. Molecular mass
C. Molecular formula
D. Formula mass
Isotopes differ in________?
A. properties, which depend upon mass
B. arrangement of electrons in orbitals
C. chemical properties
D. all of the above
Which of the following methods is used to estimate hydrogen in an organic compound?
A. Combustion method
B. Dumas method
C. Kjeldahls method
D. All of the above methods are for different purposes
The nucleus of an atom of every element will always contain____________?
A. neutrons
B. protons and electrons
C. protons
D. protons and neutrons
When 0.5 mole of phosphoric acid is dissolved in aqueous solution how many moles of -ve and +ve ions are collected altogether?
A. 0.5
B. 1
C. 1.5
D. 2
Dempsters mass spectrometer has number of zones / parts____________?
A. 5
B. 4
C. 3
D. 2
All the following variables are used to describe gases except____________?
A. pressure
B. volume
C. moles
D. density
Methyl alcohol is not used as___________________?
A. a solvent
B. an anti-freezing agent
C. a substitute for petrol
D. for denaturing of ethyl alcohol
Oxygen (molecular weight = 32) diffuses at a rate of 10cm3/min under the same conditions of temperature and pressure how fast will hydrogen (molecular weight = 2) diffuse?
A. 20cm3/min
B. 40cm3/min
C. 160cm3/min
D. 2.5cm3/min
As a substance moves from a solid to a liquid all of the following changes occur except?
A. molecules become more disordered.
B. K.E of the molecules decreases
C. intermolecular forces become weaker.
D. molecules move more frequently.
The rectified spirit is________________?
A. 12% alcohol
B. 90% alcohol
C. 95% alcohol
D. 100% alcohol
Which of the following solids show anisotropy___________________?
A. Plastic
B. Glass
C. Rubber
D. None of the above
Butyl chloride gives possible isomers?
A. 2
B. 3
C. 4
D. 5
Metallic crystals are soluble in________________?
A. Polar solvent
B. Non polar solvent
C. Fused metal
D. None
Paramagnetic behaviour of substance is measured by a balance called___________________?
A. Analytical balance
B. Guoys balance
C. Electrical balance
D. Single beam balance
Which of the following properties prove that cathode rays are material in nature_________________?
A. they cast shadow
B. they possess momentum
C. they are negatively charged
D. all of the above
When an electron is moving with velocity of 2.188 x 106 ms-1 in the first orbit of Bohrs model of hydrogen. The de Broglie wavelength of electron is______________?
A. 0.33 nm
B. 0.34 nm
C. 0.35 nm
D. 0.36 nm
When methl iodide and ethyl iodide are treated with sodium metal possible major products are obtained ?
A. 1
B. 2
C. 3
D. 4
Which statement is consistent with Hunds rule ?
A. Electrons fill orbitals with parallel spins until all the orbitals of the same energy are half filled then they go into sub-shells with anti-parallel (opposite) spin.
B. The electrons in the same atom cannot have the same four quantum numbers
C. There is maximum of two electrons is an orbital.
D. None
Atomic number of Mn is 25 what is the electronic configuration in the ground state________________?
A. 1s2 2s2 2p6 3s2 3p6 3d7
B. 1s2 2s2 2p6 3s2 3p6 4s2 4p5
C. 1s2 2s2 2p6 3s2 3p5 3d10
D. 1s2 2s2 2p6 3s2 3p6 4s23d5
Which of the following is mineral fiber ?
A. Teflon
B. asbestos
C. saran
D. acrylic
The hardest of the following solids is__________?
A. sodium
B. diamond
C. graphite
D. magnesium
Which of the solid does not contain covalent bond___________?
A. copper
B. ice
C. diamond
D. graphite
The balanced chemical equation for the reaction which occurs when Be is added to water is____________?
A. Be+2H2O?Be (OH)2+H2
B. Be+H2O?Be (OH)2+H2
C. Be+H2O?[Be (OH)4]+2+H2
D. no reaction
Which of the following theories is superior to others__________________?
A. VSEPR
B. VBT
C. MOT
D. none of the above
