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3 years ago

What are the number of protons, neutrons, and electrons in an atom of Tellurium- 129?

Chemistry

1 answer:

deff fn [24]3 years ago

3 0

Answer:

Number of protons = 52, Number of electrons = 52, Number of neutrons = 76

Explanation:

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Be sure to answer all parts. The standard enthalpy of formation and the standard entropy of gaseous benzene are 82.93 kJ/mol and

skelet666 [1.2K]

Answer : The values of $\Delta H^o,\Delta S^o\text{ and }\Delta G^o$ are $33.89kJ,95.94J/K\text{ and }5.299kJ/mol$ respectively.

Explanation :

The given balanced chemical reaction is,

$C_6H_6(l)\rightarrow C_6H_6(g)$

First we have to calculate the enthalpy of reaction $(\Delta H^o)$ .

$\Delta H^o=H_f_{product}-H_f_{reactant}$

$\Delta H^o=[n_{C_6H_6(g)}\times \Delta H_f^0_{(C_6H_6(g))}]-[n_{C_6H_6(l)}\times \Delta H_f^0_{(C_6H_6(l))}]$

where,

$\Delta H^o$ = enthalpy of reaction = ?

n = number of moles

$\Delta H_f^0_{(C_6H_6(g))}$ = standard enthalpy of formation of gaseous benzene = 82.93 kJ/mol

$\Delta H_f^0_{(C_6H_6(l))}$ = standard enthalpy of formation of liquid benzene = 49.04 kJ/mol

Now put all the given values in this expression, we get:

$\Delta H^o=[1mole\times (82.93kJ/mol)]-[1mole\times (49.04J/mol)]$

$\Delta H^o=33.89kJ/mol=33890J/mol$

Now we have to calculate the entropy of reaction $(\Delta S^o)$ .

$\Delta S^o=S_f_{product}-S_f_{reactant}$

$\Delta S^o=[n_{C_6H_6(g)}\times \Delta S^0_{(C_6H_6(g))}]-[n_{C_6H_6(l)}\times \Delta S^0_{(C_6H_6(l))}]$

where,

$\Delta S^o$ = entropy of reaction = ?

n = number of moles

$\Delta S^0_{(C_6H_6(g))}$ = standard entropy of formation of gaseous benzene = 269.2 J/K.mol

$\Delta S^0_{(C_6H_6(l))}$ = standard entropy of formation of liquid benzene = 173.26 J/K.mol

Now put all the given values in this expression, we get:

$\Delta S^o=[1mole\times (269.2J/K.mol)]-[1mole\times (173.26J/K.mol)]$

$\Delta S^o=95.94J/K.mol$

Now we have to calculate the Gibbs free energy of reaction $(\Delta G^o)$ .

As we know that,

$\Delta G^o=\Delta H^o-T\Delta S^o$

At room temperature, the temperature is $25^oC\text{ or }298K$ .

$\Delta G^o=(33890J)-(298K\times 95.94J/K)$

$\Delta G^o=5299.88J/mol=5.299kJ/mol$

Therefore, the values of $\Delta H^o,\Delta S^o\text{ and }\Delta G^o$ are $33.89kJ,95.94J/K\text{ and }5.299kJ/mol$ respectively.

6 0

3 years ago

Read 2 more answers

Only 20 plant species, such as rice, corn,and barely, make up the main sources of food for the entire human population.

riadik2000 [5.3K]

Answer:

I believe it would be D, to enhance the survival rate.

Explanation:

7 0

3 years ago

Read 2 more answers

Three elements are represented by the letters A, B, and C. the three elements have the same number of valence electrons. Element

AfilCa [17]

Answer:
A- beryllium
B- calcium
C- magnesium

Explanation
NOTE: all element in group 2 have 2 balance electrons

First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20

C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).

A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.

3 0

3 years ago

A molecule in which the central atom forms three single bonds and has one lone pair is said to have a ________ shape.

nignag [31]

Answer : The correct option is, (c) pyramidal

Explanation :

As we are given that a molecule in which the central atom forms three single bonds and has one lone pair that means the central metal atom has 3 bond pairs and 1 lone pair of electrons.

There are total 4 electron pairs. So, the hybridization will be $sp^3$ and the electronic geometry of the molecule will be tetrahedral.

But as there are three atoms or bonds around the central atom and the fourth position occupied by lone pair of electrons. The repulsion between lone and bond pair of electrons is more and hence the molecular geometry will be pyramidal.

Hence, correct option is, (c) pyramidal

5 0

3 years ago

What is the coefficient for the formula 6C6H12O6?

djyliett [7]

<span>Multiply the coefficient in front of the formula times the subscript for each element. This gives 36 carbon atoms, 72 hydrogen atoms, and 36 oxygen atoms.</span>

5 0

3 years ago