If 75.0% of the isotopes of an element have a mass of 35.0 amu and 25.0% of the isotopes have a mass of 37.0amu what is the atom

Answer:

Both CaCl2 and CaBr2 consist of elements (bromine and chlorine) from the same group (group 7).

Explanation:

In the periodic table, elements are arranged into groups based on their valence electron count in the outermost shell. Elements in the same group, which possess a similar number of valence electrons, typically exhibit similar chemical behaviors.

Chlorine and Bromine in CaCl2 and CaBr2 belong to group 7, known as HALOGENS, characterized by having 7 valence electrons in their outer shell.

The similarity in properties between CaCl2 and CaBr2 arises because both contain Chlorine and Bromine, leading to analogous reactions and behaviors when interacting with other compounds.

Answer: The vapor pressure of naphthalene within the flask remains at atm.

Explanation:

The transformation from solid naphthalene to its gaseous form follows the equilibrium reaction:

• The formula employed to determine the enthalpy change for the reaction is:  

The formula for calculating the enthalpy change regarding the aforementioned reaction is:

The provided information includes:

Substituting the values into the previous equation produces:

• The formula utilized to compute Gibbs free energy change is of a reaction:

The equation for the enthalpy change for the reaction is:

The given factors include:

By inserting values from the above equation, we arrive at:

• For the calculation of (at 25°C) regarding the provided value of Gibbs free energy, the following relationship is applied:

where,

= Gibbs free energy = 22.5 kJ/mol = 22500 J/mol  (Conversion factor: 1kJ = 1000J)

R = Gas constant =

T = temperature =

= equilibrium constant at 25°C =?

Inserting values into the above equation yields:

• To determine the equilibrium constant at 35°C, we refer to the equation proposed by Arrhenius, which states:

where,

= Equilibrium constant at 35°C =?

= Equilibrium constant at 25°C =

= Enthalpy change of the reaction = 72.1 kJ/mol = 72100 J

R = Gas constant =

= Initial temperature =

= Final temperature =

By plugging values into the equation above, we obtain:

• In order to calculate the partial pressure of naphthalene at 35°C, we utilize the equation for , which is:

The partial pressure of the solid phase is considered to be 1 at equilibrium.

Therefore, the value for will equal

Consequently, the partial pressure of naphthalene at 35°C is atm.

Answer:

The temperature of the gas rises.

Explanation:

This is classified as an ISOCHORIC process where the volume remains unchanged. There is no work done by the system.

The gas only receives internal energy from the heat transferred to it from the surroundings.

In this situation, the pressure also increases.