1
Complete and balance the following equations : Al + NaOH +___--->+

Al + 3NaOH  = Al(OH)₃ +3Na

Explanation:

The reaction is given as:

            Al + NaOH  = Al(OH)₃ + Na

This reaction is called a single displacement reaction in which one specie displaces another from a solution.

 To balance the equation:

                aAl + bNaOH  = cAl(OH)₃ + dNa

a, b, c and d are the coefficient that will balance the equation:

     Conserving Al;

                 a = c

     Conserving Na;

                b  = d

     Conserving O;

                 b  = 3c

     Conserving H;

                b = 3c

Let a  = 1, c = 1, b = 3 and d = 3

             Al + 3NaOH  = Al(OH)₃ +3Na

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"

plasma is the state of matter where the substance is ionized and has no definite shape or volume. the fact of being ionized makes the substance a good electrical conductor.