Std 6 Chemistry First Semester 2020

 

Enfant India International School

                                                          Semester I  2020-21

   Std- VI                              Subject- Chemistry                              Marks-40

                                                 Section I ( 20 marks )

Q1-Write true or false against each statement:                                                           5m

i.                    Common salt is an element.

ii.                  The symbol of nitrogen is N.

iii.                Melting of ice is a chemical change.

iv.                 Chalk powder can be separated from water by filtration.

v.                   Solids can flow easily.

  Q2-Fill in the blanks with the suitable words-                                                             5m

i-             Burning of a substance is a……….. change.

ii-            Salt can be obtained from sea water by..…….. .

iii-           …………can be compressed to some extent.

iv-           ………....is a metal which is liquid at room temperature.

v-            Most physical changes are…………….. .

Q3-Choose the correct option-                                                                                     5m

i-             Pure substances are classified as-

a.    Elements                 b. Elements and compounds

ii-            Which is a liquid metal?

a.    Iron                          b. Mercury

iii-           The liquid that passes through the filter paper is called-

a.    Residue                   b. Filtrate

iv-           The amount of space occupied by an object is called-

a.    Volume                   b. Material

v-            The molecules are very closely packed in-

a.    Solids                      b. Liquids

Q4- Give one word for the following-                                                                             5m

i.                    The short form used to represent the name of an element.__________

ii.                  A positively charged particle present in the nucleus of atom.________

iii.                A negatively charged particle present in the shell of an atom.________

iv.                 The liquid that dissolves a solid in it._____________

v.                   Anything that occupies space and has mass._____________

 

 

                                                                     Section II ( 20 marks )

Q5- Define any three of the following terms-                                                       2X3= 6m

i.                    Melting point

ii.                  Fusion

iii.                Condensation

iv.                 Atom

v.                   Molecule

Q6- Differentiate between the following-                                                              2X2= 4m

i.                    Chemical change and physical change

ii.                  Mixture and compound

Q7- Give reasons for the following-                                                                     2X2= 4m

i-             Filtration is a better method of separating an insoluble solid component as compared to decantation.

ii-            A chair is considered as solid.

Q8- Answer the following questions-                                                                   2X3= 6m

i-             How can matter be classified on the basis of chemical constitution?

ii-            What do you understand by an alloy?

iii-           Name the elements present in

A.   Sodium chloride ( NaCl )

B.   Calcium oxide ( CaO )