ANSWER QUICK 30 POINTS

For a molecule of O2 at room temperature (300 K), calculate the average angular velocity for rotations about the x or y axes. Th

Ksivusya [100]

Answer: 6.65 rad/s

Explanation:

Firstly, we need to know that according the kinetic theory of gases, the average kinetic energy $KE$ of a molecule with $i$ degrees of freedom is:

$KE=\frac{i}{2}kT$ (1)

Where:

$i=5$ because oxigen is a diatomic molecule and has 5 degrees of freedom

$k=1.38064852 (10)^{-23} \frac{m^{2}kg}{s^{2}K}$ is the Boltzman constant

$T=300 K$ is the temperature

Then:

$KE=\frac{5}{2}(1.38064852 (10)^{-23} \frac{m^{2}kg}{s^{2}K})(300 K)$ (2)

$KE=1.035 (10)^{-20} \frac{m^{2}kg}{s^{2}}$ (3) With this value of average kinetic energy we can find the average angular velocity, with the following equation:

$KE=\frac{1}{2}I \omega^{2}$ (4)

Where:

$I$ is the moment of inertia

$\omega$ is the angular velocity

Now, $I=m R^{2}$ (5)

Being $m=31.98 g/mol=0.03198 kg/mol$ the molar mass of Oxigen molecule and $R=0.121(10)^{-9}m$ the distance between atoms

$I=(0.03198 kg/mol)(0.121(10)^{-9}m)^{2}$ (6)

$I=4.682(10)^{-22} \frac{kg}{mol} m^{2}$ (7)

Substituting (7) and (3) in (4):

$1.035 (10)^{-20} \frac{m^{2}kg}{s^{2}}=\frac{1}{2} (4.682(10)^{-22} \frac{kg}{mol} m^{2}) \omega^{2}$ (8)

Finding $\omega$ :

$\omega=6.65 rad/s$ (9) This is the average angular velocity for a molecule of O2

7 0

3 years ago

Which list includes the phase changes that require a loss of energy (heat)?

Lemur [1.5K]

Answer:

b

Explanation:

because if you freeze somthing you do not gain heat you loss heat.

3 0

2 years ago

If the atoms that share electrons have an unequal attraction for the electrons is called

Karolina [17]

If the atoms that share electrons have an unequal attraction for electrons, the bond is called a Polar covalent bond.

<h3><u>Explanation:</u></h3>

A covalent chemical bond is formed in case of two different non-metals when one or more electron pairs are shared between bonding atoms. A difference in electronegativity of subsequent atoms of a covalent bond leads to formation of a small net charge around nucleus of each atom, pulling the shared electrons to one side of the bond, to the nucleus which has higher electronegativity.

HCl is an example of polar covalent bond and the HCl bond has Chlorine more electronegative. The bonding electrons are more close to Cl than H and hence Cl is partially negatively charged than H which has partial positive charge (HCl bond : $H^{+} - Cl^{-}$ ). When electrons shared in a covalent bond have equal attraction, the bond is a Non-Polar covalent bond.