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3 years ago

I need help with Hess law

Chemistry

1 answer:

ICE Princess25 [194]3 years ago

6 0

Answer:

alright

Explanation:

Hess law is the enthalpy change for a reaction that is carried out in a series of steps is equal to the sum of the enthalpy changes for the individual steps. Consistent with the law of conservation of energy. Starting and final conditions must be the same.

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Consider the following reaction: CO(g)+2H2(g)⇌CH3OH(g) This reaction is carried out at a different temperature with initial conc

Anni [7]

Answer:

Ka = 4.76108

Explanation:

CO(g) + 2H2(g) ↔ CH3OH(g)

∴ Keq = [CH3OH(g)] / [H2(g)]²[CO(g)]

[ ]initial change [ ]eq

CO(g) 0.27 M 0.27 - x 0.27 - x

H2(g) 0.49 M 0.49 - x 0.49 - x

CH3OH(g) 0 0 + x x = 0.11 M

replacing in Ka:

⇒ Ka = ( x ) / (0.49 - x)²(0.27 - x)

⇒ Ka = (0.11) / (0.49 - 0.11)² (0.27 - 0.11)

⇒ Ka = (0.11) / (0.38)²(0.16)

⇒ Ka = 4.76108

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3 years ago

Does the hydrogen molecule obey the octet rule?

Alja [10]

Explanation:

Hydrogen does not obey the octet rule. Boron does not always

obey the octet rule and in fact forms Lewis acids such as BF3 which

only has 6 electrons.

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3 years ago

What properties can be used to identify substance and why?

Elena L [17]

Answer:

All substances can be characterized by their unique sets of physical and chemical properties. Properties that can be determined without changing the composition of a substance are referred to as physical properties. Characteristics such as melting point, boiling point, density, solubility, color, odor, etc.

3 0

3 years ago

Part 1: What is the final volume in milliliters when 0.730 L of a 44.8 % (m/v) solution is diluted to 23.3 % (m/v)?

Andre45 [30]

part 1 : the final volume : 1.404 L

part 2 : the initial concentration : 4.06 M

<h3>Further explanation </h3>

Dilution is the process of adding a solvent to get a more dilute solution.

The moles(n) before and after dilution are the same.

Can be formulated :

M₁V₁=M₂V₂

M₁ = Molarity of the solution before dilution

V₁ = volume of the solution before dilution

M₂ = Molarity of the solution after dilution

V₂ = Molarity volume of the solution after dilution

part 1 :

M₁=44.8%

V₁=0.73 L

M₂=23.3%

$\tt V_2=\dfrac{M_1.V_1}{M_2}\\\\V_2=\dfrac{44.8\times 0.73}{23.3}\\\\V_2=1.404~L$

part 2 :

V₁=739 ml=0.739 L

V₂=1.5 L

M₂=2

$\tt M_1=\dfrac{M_2.V_2}{V_1}\\\\M_1=\dfrac{2\times 1.5}{0.739}\\\\M_1=4.06$

6 0

3 years ago

The value of Ka for phenol (a weak acid), C6H5OH, is 1.00×10-10. Write the equation for the reaction that goes with this equilib

I am Lyosha [343]

Answer:

$Ka=\frac{[C_6H_5O^-][H^+]}{[C_6H_5OH]}$

Explanation:

Hello,

In this case, weak acids are characterized by the fact they do not dissociate completely, it means they do not divide into the conjugated base and acid at all, a percent only, which is quantified via equilibrium. In such a way, the chemical equation representing such incomplete dissociation is said to be:

$C_6H_5OH\rightleftharpoons C_6H_5O^-+H^+$

Thus, we can write the law of mass action, which consider the equilibrium concentrations of all the involved species, which is also known as the acid dissociation constant which accounts for the capacity the acid has to yield hydronium ions:

$K=Ka=\frac{[C_6H_5O^-][H^+]}{[C_6H_5OH]}$

Best regards.

3 0

3 years ago