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2 years ago

What is the atomic number of an atom woth six valence electrons?(A) 8(B)10(C) 12

Chemistry

1 answer:

Alexxx [7]2 years ago

5 0

Answer:

Explanation:

The atomic mass of an atom refers to the number of protons in the nucleus of an atom. Hence, an element with 6 valence electron mean that it has 6 electrons in its outermost shell.

The atomic Number of elements with 6 valence electrons cannot necessarily be the same, however, elements with 6 valence electrons belong to group six on the periodic table.

From the options given above, :

Atomic number of 8 :

Configuration : 2, 6

Atomic number of 10 :

Configuration : 2, 8

Atomic number of 12 :

Configuration : 2, 8, 2

Hence, only the element with atomic number of 8 has 6 valence electrons in its outer most shell, hence, the answer.

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If the mixing ratio of a parcel of air is 6 grams per kilogram and the relative humidity is 25 percent, the saturation mixing ra

Y_Kistochka [10]

Answer: -

24 grams per kilogram.

Explanation: -

We know that

The mixing ratio = actual (measured) mass of water vapor (in parcel) in grams / mass of dry (non water vapor) air (in parcel) in kilogram

The saturation mixing ratio = mass of water vapor required for saturation (in parcel) in grams/ mass of dry (non water vapor) air (in parcel) in kilograms

Relative humidity = actual (measured) water vapor content/ maximum possible water vapor amount (saturation)

Thus saturation mixing ratio = Mixing ratio / relative humidity

= 6 / (25/100)

= 24

4 0

3 years ago

Given that ΔH = −571.6 kJ/mol for the reaction 2 H2(g) + O2(g) → 2 H2O(l), calculate ΔH for these reactions. (a) 2 H2O(l) → 2 H2

pashok25 [27]

Answer : The value of $\Delta H$ for the reaction is +571.6 kJ/mole.

Explanation :

According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.

According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.

The given chemical reaction is,

$2H_2(g)+O_2(g)\rightarrow 2H_2O(l)$ $\Delta H_1=-571.6kJ/mole$

Now we have to determine the value of $\Delta H$ for the following reaction i.e,

$2H_2O(l)\rightarrow 2H_2(g)+O_2(g)$ $\Delta H_2=?$

According to the Hess’s law, if we reverse the reaction then the sign of $\Delta H$ change.

So, the value $\Delta H_2$ for the reaction will be:

$\Delta H_2=-(-571.6kJ/mole)$

$\Delta H_2=+571.6kJ/mole$

Hence, the value of $\Delta H$ for the reaction is +571.6 kJ/mole.

6 0

2 years ago

How many grams of XeF6 are required to react with 0.579 L of hydrogen gas at 6.46 atm and 45°C in the reaction shown below?

ankoles [38]

The chemical reaction equation for this is

XeF6 + 3H2 ---> Xe + 6HF

Assuming gas behaves ideally, we use the ideal gas formula to solve for number of moles H2 with T = 318.15K (45C), P = 6.46 atm, V = 0.579L. Then we use the gas constant R = 0.08206 L atm K-1 mol-1.

we get n = 0.1433 moles H2

to get the mass of XeF6,

we divide 0.1433 moles H2 by 3 since 1 mole XeF6 needs 3 moles H2 to react then multiply by the molecular weight of XeF6 which is 245.28 g/mole XeF6.

0.1433 moles H2 x $\frac{1 mole XeF6}{3 moles H2}$ x $\frac{245.28 g XeF6}{1 mole XeF6}$ = 11.71 g XeF6

Therefore, 11.71 g of XeF6 is needed to completely react with 0.579 L of Hydrogen gas at 45 degrees Celcius and 6.46 atm.

3 0

3 years ago

At the same temperature, steam burns are often more severe than water burns because of water's high A. polarity B. heat of vapor

aivan3 [116]

Because of eater's high is A

5 0

3 years ago

If the equilibrium constant of the reaction is 0.85, then which statement is true if the mass of A is 10.5 grams; the density of

snow_tiger [21]

Answer:

E. Q < K and reaction shifts right

Explanation:

Step 1: Write the balanced equation

A(s) + 3 B(l) ⇄ 2(aq) + D(aq)

Step 2: Calculate the reaction quotient (Q)

The reaction quotient, as the equilibrium constant (K), only includes aqueous and gaseous species.

Q = [C]² × [D]

Q = 0.64² × 0.38

Q = 0.15

Step 3: Compare Q with K and determine in which direction will shift the reaction

Since Q < K, the reaction will shift to the right to attain the equilibrium.

8 0

2 years ago

What is the atomic number of an atom woth six valence electrons?(A) 8(B)10(C) 12​

What is the atomic number of an atom woth six valence electrons?(A) 8(B)10(C) 12