Question: dimethylhydrazine, the
fuel used in the apollo lunar descentmodule, has a molar mass of
60.10 g/mol. it is made up of carbon, hydrogen, and nitrogen atoms.
the combustion of 2.859g of the fuelin excess oxygen yields 4.190g
of carbon dioxideand 3.428g ofwater. what are the simplest and
molecular formulas fordimethylhydrazine?

Explanation:

Given parameters:

Molar mass of compound = 60.1g/mol

Mass of fuel used in the combustion process = 2.859g

Mass of carbon dioxide produced = 4.190g

Mass of oxygen produced= 3.428g

Unknown parameters;

Empirical and molecular formula of the compound

Solution

The empirical formula of a compound is its simplest formula. The molecular formula is the actual formula of the compound showing the proportions of the atoms.

We can derive the empirical formula of a compound from its molecular formula and vice versa.

Here, we have to work from empirical formula to molecular formula.

Solving

For Carbon, we can determine the mass from the amount of carbon dioxide produced:

       mass of carbon in compound = x 4.19g = 1.14g

For Hydrogen, we can determine the mass from the amount of water produced:      

   mass of hydrogen in compound = x 3.428g = 0.38g

To determine the mass of N in the compound:

 mass of compound = mass of C + mass of H + mass of N

   mass of N = mass of compound - (mass of C + mass of H)

    mass of N = 2.859g - (1.14g + 0.38g) = 1.34g

2. we now proceed to find the empirical formula using the process below:

Elements                C                          H                       N

mass of the

elements                1.14                      0.38                 1.34

Atomic mass

of elements             12                           1                        14

Number of

moles                     1.14/12                  0.38/1                1.34/14

                              0.095                    0.38                   0.095

Dividing by

the smallest        0.095/0.095       0.38/0.095          0.095/0.095

                                1                                4                           1

The empirical formula of the compound is CH₄N

To obtain the molecular formula, we need to find the number of times the empirical formula must have repeated itself in the original form.

 Molar mass of CH₄N = 12 + 4 + 14 = 30g/mol

  Ratio = = = 2

Molecular formula = 2(CH₄N) = C₂H₈N₂

question: ray weighs 100 kilograms, his wrestling partner, bobby, weighs 50 kilograms. if ray moves at 4 m s , how fast will bobby have to run at him to apply an equal amount of kinetic energy?

answer: 8 m/s he needs to run twice as fast to keep up so he has some work to do

explanation:   if the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.

question answered by

(jacemorris04)