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3 years ago

The electron configuration for an atom is 1s 2s 2p2. How many electrons does the atom have?

Chemistry

1 answer:

taurus [48]3 years ago

7 0

Answer:

Four

Step-by-step explanation:

The superscripts in an electron configuration tell us how many electrons are in a subshell.

If the electron configuration is 1s¹ 2s¹2p², the total number of electrons is

1 + 1 + 2 = 4

The atom contains four electrons.

Note: this atom is in an excited state, because the 1s and 2s subshells can each hold one more electron.

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For the reaction Fe3O4(s) + 4H2(g) --> 3Fe(s) + 4H2O(g)

mojhsa [17]

Answer : The value of equilibrium constant for this reaction at 328.0 K is $1.70\times 10^{15}$

Explanation :

As we know that,

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

where,

$\Delta G^o$ = standard Gibbs free energy = ?

$\Delta H^o$ = standard enthalpy = 151.2 kJ = 151200 J

$\Delta S^o$ = standard entropy = 169.4 J/K

T = temperature of reaction = 328.0 K

Now put all the given values in the above formula, we get:

$\Delta G^o=(151200J)-(328.0K\times 169.4J/K)$

$\Delta G^o=95636.8J=95.6kJ$

The relation between the equilibrium constant and standard Gibbs free energy is:

$\Delta G^o=-RT\times \ln k$

where,

$\Delta G^o$ = standard Gibbs free energy = 95636.8 J

R = gas constant = 8.314 J/K.mol

T = temperature = 328.0 K

K = equilibrium constant = ?

Now put all the given values in the above formula, we get:

$95636.8J=-(8.314J/K.mol)\times (328.0K)\times \ln k$

$k=1.70\times 10^{15}$

Therefore, the value of equilibrium constant for this reaction at 328.0 K is $1.70\times 10^{15}$

3 0

3 years ago

At which of the following temperatures does all molecular motion stop

Kamila [148]

All molecular motion stop at 0 k wich is zero kelvin. At absolute 0 it stops. The temperature of 0 entropy at which all molecular motion stops equals in centigrades to -273.15° C which is the same as 0 in kelvin degrees. Have in mind that temperature is a measure of the average kinetic energy of the molecules in a material.

3 0

3 years ago

Given the reaction: A + B <--> C + D

Lady_Fox [76]

Answer:

A.) 4.0

Explanation:

The general equilibrium expression looks like this:

$K = \frac{[C]^{c} [D]^{d} }{[A]^{a} [B]^{b} }$

In this expression,

-----> K = equilibrium constant

-----> uppercase letters = molarity

-----> lowercase letters = balanced equation coefficients

In this case, the molarity's do not need to be raised to any numbers because the coefficients in the balanced equation are all 1. You can find the constant by plugging the given molarities into the equation and simplifying.

$K = \frac{[C]^{c} [D]^{d} }{[A]^{a} [B]^{b} }$ <----- Equilibrium expression

$K = \frac{[2 M] [2 M]}{[1 M] [1 M] }$ <----- Insert molarities

$K = \frac{4}{1 }$ <----- Multiply

$K = 4$ <----- Divide

6 0

2 years ago

The region in which an electron is likely to be found is known as a(n) ____________.

Zinaida [17]

Answer:

orbital

Explanation:

electrons are found in an orbital

3 0

3 years ago

A scientist investigates a new substance and finds that at 35° C, 146.2 grams will dissolve in 200.0 grams of water. Which simil

Nimfa-mama [501]

The scientist's results is that at a temperature of 35°C, the solubility of the substance in water is 146.2 grams in 200 grams of water. There isn't really a different method to determine the solubility of a substance in water. Another procedure could be that a lesser amount of the substance is used and the water required to dissolve it is determined. The solubility of the substance based on the two procedures can then be compared.

5 0

3 years ago