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postnew [5]
3 years ago
15

Please can someone explain the reason Iron has 2 or 3 valence electrons​

Chemistry
1 answer:
DochEvi [55]3 years ago
8 0

Answer: The electronic configuration of iron is: Ar3d64s2. the two electrons in the 4s orbital are paired, and two of the electrons in the 3d orbitals are paired leaving four unpaired electrons.

Explanation:

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Suppose 2.8 moles of methane are allowed to react with 5 moles of oxygen.
Ronch [10]

Answer : The limiting reagent is O_2

Solution : Given,

Moles of methane = 2.8 moles

Moles of O_2 = 5 moles

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

CH_4+2O_2\rightarrow CO_2+2H_2O

From the balanced reaction we conclude that

As, 2 mole of O_2 react with 1 mole of CH_4

So, 5 moles of O_2 react with \frac{5}{2}=2.5 moles of CH_4

From this we conclude that, CH_4 is an excess reagent because the given moles are greater than the required moles and O_2 is a limiting reagent and it limits the formation of product.

Hence, the limiting reagent is O_2

8 0
4 years ago
A photon of light possesses 5 x 10^-19 J of energy. Calculate its frequency
saveliy_v [14]

Answer:

The frequency of photon is 0.75×10¹⁵ s⁻¹.

Explanation:

Given data:

Energy of photon = 5×10⁻¹⁹ J

Frequency of photon = ?

Solution:

Formula;

E = hf

h = planck's constant = 6.63×10⁻³⁴ Js

5×10⁻¹⁹ J =  6.63×10⁻³⁴ Js ×f

f =  5×10⁻¹⁹ J / 6.63×10⁻³⁴ Js

f = 0.75×10¹⁵ s⁻¹

The frequency of photon is 0.75×10¹⁵ s⁻¹.

4 0
3 years ago
The combustion of 44.45 grams of a hydrocarbon gas mixture releases 2,649 kJ of heat. How much energy, in kWh, will the combusti
Naddika [18.5K]

Explanation:

It is given that 44.45 g of hydrocarbon gas produces 2649 kJ or 2649 \times 10^{3} J of heat.

Also here, 1 lb = 453.592 g.

Therefore, amount of energy released by 453.592 g of hydrocarbon gas will be calculated as follows.

              \frac{2649 \times 10^{3} J \times 453.592 g}{44.45 g}

             = 27.03 \times 10^{6} J

It is known that 1 J = 2.778 \times 10^{-7} Kwh.

Hence, 27.03 \times 10^{6} J = 27.03 \times 10^{6} J \times 2.778 \times 10^{-7} Kwh/J

                              = 7.508 Kwh

Thus, we can conclude that the combustion of exactly one pound of this hydrocarbon gas produce 7.508 Kwh energy.

3 0
3 years ago
The _______ force between each planet and the Sun keeps the planets in orbit around the Sun.
nata0808 [166]
The answer will be the gravitational force, because if we weren't in the gravity of the sun we would also be floating around with not much purpose.
8 0
3 years ago
Read 2 more answers
Can you name some chemical elements you use or see on a regular basis?
kaheart [24]

Answer:

Hydrogen. Symbol: H. Atomic Weight: 1.008. ...

Magnesium. Symbol: Mg. Atomic Weight: 24.305. ...

Aluminum. Symbol: Al. Atomic Weight: 26.9815385. ...

Phosphorus. Symbol: P. ...

Chlorine. Symbol: Cl. ...

Argon. Symbol: Ar. ...

Potassium. Symbol: K. ...

Calcium. Symbol: Ca.

4 0
3 years ago
Read 2 more answers
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