Calculate the number of ions present in 8.2 moles of calcium nitrate

             1.48 × 10²⁵ Ions

Solution:

Calcium Nitrate having a chemical formula Ca(NO₃)₂ is made up of one Ca²⁺ cation and two NO₃⁻ anions. Hence, we can say that each Calcium Nitrate contains three ions respectively.

Therefore,

                1 mole of Ca(NO₃)₂ contains  =  6.022 × 10²³ formula Units

So,

       8.2 mole of Ca(NO₃)₂ will contain  =  X Formula Units

Solving for X,

                      X =  (8.2 mol × 6.022 × 10²³ formula units) ÷ 1 mol

                      X =  4.93 × 10²⁴ Formula Units

As discussed,

                      1 Formula Unit of Ca(NO₃)₂ contains  =  3 Ions

So,

                    4.93 × 10²⁴ Formula units will contain  =  X ions

Solving for X,

                      X =  (4.93 × 10²⁴ Formula Unit × 3 Ions) ÷ 1 Formula Unit

                      X  =  1.48 × 10²⁵ Ions

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.