Suppose that the average velocity (v rms) of carbon dioxide molecules (molecular mass is equal to 44 g/mole) in a flame is found to be 1050 m/s. What temperature does this represent?

Respuesta :

Given:

The molecular mass of the molecule is

[tex]M=44\text{ g/mole}[/tex]

The speed of the molecule is

[tex]v=1050\text{ m/s}[/tex]

Required: The temperature of the molecule is

Explanation:

we know that root mean square velocity of the molecule is given as

[tex]v=\sqrt[2]{\frac{3kN_AT}{M}}[/tex]

Here, k is Boltzmann's constant and m is the mass of the molecule in grams and T is the temperature and

[tex]N_A=6.023\times10^{23}\text{ mole}^{-1}[/tex][tex]k=1.38\times10^{-23}\text{ J/K}[/tex]

we have to find T then square the above relation and simply for T

[tex]\begin{gathered} v=\sqrt[2]{\frac{3kN_AT}{M}} \\ v^2=\frac{3kN_AT}{M} \\ T=\frac{v^2M}{3kN_A} \end{gathered}[/tex]

now change the molecular mass into standard units

[tex]\begin{gathered} M=44\text{ g/mole}\times\frac{1\text{ kg}}{10^3\text{ g}} \\ M=0.044\text{ kg/mole} \end{gathered}[/tex]

now plugging all the values in the above relation we get

[tex]\begin{gathered} T=\frac{v^{2}M}{3kN_{A}} \\ T=\frac{(1050\text{ m/s})^2\times0.044\text{ kg/mole }}{3\times1.38\times10^{-23}\text{ J/K}\times6.023\times10^{23}\text{ mole}^{-1}} \\ T=\frac{48510}{24.93522} \\ T=1945.44\text{ K} \end{gathered}[/tex]

Thus, the Temperature of the molecule is

[tex]1945.44\text{ K}[/tex]