All categories

3 years ago

What is a molecule???

1 answer:

6 0

A molecule consists of group of atoms that are bonded together by chemical bond. It is the smallest particle of an element or a compound that has the properties of the element or the compound embedded in it. The atoms present in one element easily forms a bonding with the atoms of another element to form molecules. The size and complex nature of molecules varies hugely. Some molecules can have a single atom as is the case with helium, while in several other elements the number of atoms in the molecule can be more than one.

You might be interested in

Nitric oxide (NO) from car exhaust is a primary air pollutant. Calculate the equilibrium constant for the reaction

viva [34]

This problem is asking for the equilibrium constant at two different temperatures by describing the chemical equilibrium between gaseous nitrogen, oxygen and nitrogen monoxide at 25 °C and 1496 °C as the room temperature and the typical temperature inside the cylinders of a car's engine respectively:

N₂(g) + O₂(g) ⇄ 2 NO(g)

Thus, the calculated equilibrium constants turned out to be 6.19x10⁻³¹ and 9.87x10⁻⁵ at the aforementioned temperatures, respectively, according to the following work:

There is a relationship between the Gibbs free energy, enthalpy and entropy of the reaction, which leads to the equilibrium constant as shown below:

$\Delta _rG=\Delta _rH-T\Delta _rS\\\\\Delta _rG=-RT ln(K)$

Which means we can calculate the enthalpy and entropy of reaction and subsequently the Gibbs free energy and equilibrium constant. In such a way, we calculate these two as follows, according to the enthalpies of formation and standard entropies of N₂(g), O₂(g) and NO(g) since these are assumed constant along the temperature range:

$\Delta _rH=2*90.25 kJ/mol - (0 kJ/mol+0 kJ/mol)=180.5kJ/mol\\\\\Delta _rS=2*(0.211 kJ/mol*K)-(0.192kJ/mol*K+0.205kJ/mol*K)=0.025kJ/mol*K$

Then, we calculate the Gibbs free energy of reaction at both 25 °C and 1496 °C:

$\Delta _rG_{25\°C}=180.5-(25+298.15)*0.025=172.42kJ/mol\\\\\Delta _rG_{1496\°C}=180.5-(1496+298.15)*0.025=135.65kJ/mol$

And finally, the equilibrium constants derived from the general Gibbs equation and Gibbs free energies of reaction:

$K=exp(-\frac{\Delta _rG}{RT} )\\\\K_{25\°C}=exp[-\frac{172420 J/mol}{(8.3145\frac{J}{mol*K})(298.15K)} ]=6.19x10^{-31}\\\\K_{1496\°C}=exp[-\frac{135650J/mol}{(8.3145\frac{J}{mol*K})(1769K)} ]=9.87x10^{-5}$

Learn more:

(Gibbs free energy) brainly.com/question/15213613

4 0

3 years ago

choose five elements from the periodic table and arrange them according to increasing atomic radii increasing ionization energy

gregori [183]

Choose five elements from the periodic table and arrange them according to increasing atomic radii increasing ionization energy increasing electronegativity in increasing metallic property

6 0

3 years ago

4. An atom is neutral because it has the same number of protons as it has:

stealth61 [152]

Neutrons the way this question is setup the atom would not be able to be neutral

7 0

3 years ago

Consider the aldol-dehydration reaction. Draw the two possible products of the reaction between benzaldehyde and methylethylketo

Dafna1 [17]

Solution :

An $\text{aldol condensation}$ reaction is a type of $\text{condensation reaction}$ in organic chemistry where the enol or an enolate ion reacts with the carbonyl compound and forms a $\beta$ -hydroxyaldehyde or a $\beta$ -hydroxyketone, and then followed by a dehydration to give conjugated enone.

Benzaldehyde reacts with methylketone and forms two products:

5 0

3 years ago

If there is 25.0 L of gas at a temperature of 350C what is the temperature if the volume increases to 75.0L?

Zielflug [23.3K]

Answer:

The new temperature is 1596 C.

Explanation:

Charles's Law indicates that for a given sum of gas at constant pressure, as the temperature increases, the volume of the gas increases, and as the temperature decreases, the volume of the gas decreases.

Statistically, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the ratio that exists between the volume and the temperature will always have the same value:

$\frac{V}{T}=k$