Q 1 – If we put camphor in an open container, its amount keeps on decreasing due to the phenomenon of.
(a) Evaporation
(b) Precipitation
(c) Condensation
(d) Sublimation
Q 2 – A pure substance that is made up of only one kind of atom and cannot be broken into two or simpler substances by physical or chemical means is referred to as
(a) a compound
(b) an element
(c) a molecule
(d) a mixture
Q 3 – Which of the following non-metal is a good conductor of electricity?
(a) Aluminium
b) Silicon
(c) Graphite
(d) Gold
Q 4 – Which of the following property does not describe a compound?
(a) It is composed of two or more elements
(b) It is a pure substance.
(c) It cannot be separated into constituents by physical means
(d) It is mixed in any proportion by mass
Q 5 – How one can separate ammonium chloride from a mixture containing ammonium chloride and sodium chloride?
(a) Precipitation
(b) Sublimation
(c) Chromatography
(d) Centrifugation
Q 6 –According to the definition of pure substance, which of the following is a pure substance?
(a) Ice
(b) Mercury
(c) Iron
(d) All of these
Q 7 – Which of the following is a compound?
(a) Stainless steel
(b) Bronze
(c) Hydrogen Sulphide
(d) Graphite
Q 8 – Which of the following metals is/are melts on our palm:
(a) Bromine
(b) Gallium
(c) Cesium
(d) Mercury
Q 9 – Air is regarded as a mixture because:
(a) Its pressure may very
(b) Its temperature may change
(c) Its volume changes under different conditions
(d) Its composition may vary
Q 10 –The process used to separate oil and water is:
(a) Distillation
(b) Sublimation
(c) Separating funnel
(d) chromatography
Q 11 – A mixture of common salt, sulfur, sand, and iron filings is shaken with carbon disulfide and filtered through a filter paper. The filtrate is evaporated to dryness in a china dish. What will be left in the dish after evaporation?
(a) Sand
(b) Sulphur
(c) Iron filings
(d) Common salt
Q 12 – Two substances A and B when bought together form a substance C with the evolution of heat. The properties of C are entirely different from those of A and B. the substance C is:
(a)A compound
(b)An element
(c)A mixture
(d)None of the above
Q 13 – Which one of the following will result in the formation of a mixture?
(a) Crushing of a marble tile into small particles
(b) Breaking of ice cubes into small pieces
(c) Adding sodium metal to water
(d) Adding milk to water
Q 14 – The purity of a solid substance can be checked by its:
(a) Boiling point
(b) Melting point
(c) Solubility in water
(d) Solubility in alcohol
Q 15 – Compounds:
(a)Are they the same as mixtures?
(b)Can be separated by their physical properties
(c)Contain only one type of element
(d)Are different kinds of atoms chemically combined with each other?
Q 16 – A sample contains two substances and has uniform properties. The sample is:
(a) A compound
(b) A heterogeneous mixture
(c) An element
(d) A homogeneous mixture
Q 17 – A mixture of ZnCl2 and PbCl2 can be separated by:
(a) Distillation
(b) Crystallization
(c) Sublimation
(d) Adding acetic acid