Which of the following molecules/ions has a pyramid shape?

What is another name for the molecular orbital theory of bonding in metals? band theory ionic bond theory covalent bond theory e

mote1985 [20]

Band theory

The atomic orbitals of metals combine to form molecular orbitals. The molecular orbitals are so close in energy that they form a band of energies.

Ionic bond theory is incorrect because there are no ions in metals.

Covalent bond theory is incorrect because there are no covalent bonds in metals.

Electron bond theory is incorrect because there is no theory with that name (but there is a valence bond theory).

4 0

3 years ago

Read 2 more answers

Coal gasification is a multistep process to convert coal into cleaner-burning fuels. In one step, a coal sample reacts with supe

ddd [48]

Answer :

The enthalpy of reaction is, -187.6 kJ/mol

The total heat will be, -2251 kJ

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.

(a) The formation of $CH_4$ will be,

$2C(coal)+2H_2O(g)\rightarrow CH_4(g)+CO_2(g)$ $\Delta H_{rxn}=?$

The intermediate balanced chemical reaction will be,

(1) $C(coal)+H_2O(g)\rightarrow CO(g)+H_2(g)$ $\Delta H_1=29.7kJ$

(2) $CO(g)+H_2O(g)\rightarrow CO_2(g)+H_2(g)$ $\Delta H_2=-41kJ$

(3) $CO(g)+3H_2(g)\rightarrow CH_4(g)+H_2O(g)$ $\Delta H_3=-206kJ$

We are multiplying equation 1 by 2 and then adding all the equations, we get :

(b) The expression for enthalpy of reaction will be,

$\Delta H_{rxn}=2\times \Delta H_1+\Delta H_2+\Delta H_3$

$\Delta H_{rxn}=(2\times 29.7)+(-41)+(-206)$

$\Delta H_{rxn}=-187.6kJ/mol$

Therefore, the enthalpy of reaction is, -187.6 kJ/mol

(c) Now we have to calculate the total heat.

$\Delta H=\frac{q}{n}$

or,

$q=\Delta H\times n$

where,

$\Delta H$ = enthalpy change = -187.6 kJ/mol

q = heat = ?

n = number of moles of coal = $\frac{1.00\times 1000g}{12.00g/mol}=83.33mol$

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

$q=(-187.6kJ/mol)\times (83.33mol)=-2.251kJ$

Thus, the total heat will be, -2251 kJ

4 0

4 years ago

Stars making a circular motion across the sky is evidence of

lutik1710 [3]

Answer:

because they are actually moving, or because they reflect our motion through space.

7 0

3 years ago

Read 2 more answers

Are two double bonds in uble dash. :0=C=O NO2-

LenaWriter [7]

Answer:

Yes

Explanation:

There are in double dash :) ( = )

5 0

3 years ago

Read 2 more answers

Write a balanced equation using the correct formulas and include conditions (s, l, g or aq) for each of the following reactions.

Aloiza [94]

Answer:

2Fe(s) + 3Cl2(g) → 2FeCl3(s)

Explanation:

Step 1: Data given

iron = Fe = solid = Fe(s)

chlorine = Cl2 = gas = Cl2(g)

iron(III) chloride = FeCl3 = solid = FeCl3(s)

Step 2: The unbalanced equation

Fe(s) + Cl2(g) → FeCl3(s)

Step 3: Balancing the equation

Fe(s) + Cl2(g) → FeCl3(s)

On the left we have 2x Cl (in Cl2) and on the right side we have 3x Cl (in FeCl3). To balance the amount of Cl we have to multiply Cl2 (on the left) by 3 and FeCl3 by 2.

Fe(s) + 3Cl2(g) → 2FeCl3(s)

On the left side we have 1x Fe and on the right side we have 2x Fe (in 2FeCl3). To balance the amount of Fe, we have to multiply Fe on the left side by 2. Now the equation is balanced.

2Fe(s) + 3Cl2(g) → 2FeCl3(s)

6 0

4 years ago