KUIZ KIMIA

Table 1 shows the proton numbers of 2 elements,P and Q

ELEMENTS                    PROTON NUMBERS

      P                                                9

      Q                                               12

(a)     Draw the atomic structure of atom  P.

(b) (i) The atom of element P has isotopes. What meant by isotopes?

     (ii) State one example of isotopes.

 (c) (i) The atom of element Q has a nucleon numbers of 24.Calculate the numbers of nucleon.

      (ii) Write the standard representation of atom Q.

(d) Ammonia has melting point of -78c and boiling point of 33c

  

   (i) What is the physical state of ammonia at room temperature?

   (ii)Draw the arrangement of particles of ammonia at 0c

   (iii) Sketch the graph of temperature against time when ammonia heated from -100c to 0c.

THREE TYPES OF PARTICLES

Particles forming matter

Atom    :

             The simplest form of particles (basic unit of mater)

Example:

             All metals and some non-metals,such as graphite and diamond are made up of only one type of atom

Molecule: 

              Particles made up of a combination of two or more atoms in certain arrangements through     chemical bonds

Example:

              Almost all non-metal elements such as bromine Br2,napthalene,benzene,C6H6,and water,H2O,are made of molecules

Ion       :

              Particles made of atoms which receive or lose electrons

Example:

              Ionic subtances such as sodium chloride,NaCl, lead (II) bromide, PbBr2, and potassium  hydroxide,KOH, are made up of ions.