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2 years ago

Which statement is true for an open system?

Chemistry

1 answer:

Bingel [31]2 years ago

3 0

Answer:

Before we get into the first law of thermodynamics we need to understand the relation between heat and work and the concept of internal energy. Just like mass, energy is always conserved i.e. it can neither be created nor destroyed but it can be transformed from one form to another. Internal energy is a thermodynamic property of the system that refers to the energy associated with the molecules of the system which includes kinetic energy and potential energy.

Whenever a system goes through any change due to interaction of heat, work and internal energy, it is followed by numerous energy transfer and conversions. However, during these transfers, there is no net change in the total energy.

Similarly, if we look at the first law of thermodynamics it affirms that heat is a form of energy. What it means is that the thermodynamic processes are governed by the principle of conservation of energy. The first law of thermodynamics is also sometimes referred to as the Law of Conservation of Energy

Explanation:

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An<br> a transition metal with 91 protons and electrons?

ser-zykov [4K]

Protactinium

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6 0

3 years ago

Read 2 more answers

The activation energy for a reaction is changed from 184 kJ/mol to 59.0 kJ/mol at 600. K by the introduction of a catalyst. If t

11111nata11111 [884]

Answer:

The catalyzed reaction will take 2.85 seconds to occur.

Explanation:

The activation energy of a reaction is given by:

$k = Ae^{-\frac{E_{a}}{RT}}$

For the reaction without catalyst we have:

$k_{1} = Ae^{-\frac{E_{a_{1}}}{RT}}$ (1)

And for the reaction with the catalyst:

$k_{2} = Ae^{-\frac{E_{a_{2}}}{RT}}$ (2)

Assuming that frequency factor (A) and the temperature (T) are constant, by dividing equation (1) with equation (2) we have:

$\frac{k_{1}}{k_{2}} = \frac{Ae^{-\frac{E_{a_{1}}}{RT}}}{Ae^{-\frac{E_{a_{2}}}{RT}}}$

$\frac{k_{1}}{k_{2}} = e^{\frac{E_{a_{2}} - E_{a_{1}}}{RT}$

$\frac{k_{1}}{k_{2}} = e^{\frac{59.0 \cdot 10^{3}J/mol - 184 \cdot 10^{3} J/mol}{8.314 J/Kmol*600 K} = 1.31 \cdot 10^{-11}$

Since the reaction rate is related to the time as follow:

$k = \frac{\Delta [R]}{t}$

And assuming that the initial concentrations ([R]) are the same, we have:

$\frac{k_{1}}{k_{2}} = \frac{\Delta [R]/t_{1}}{\Delta [R]/t_{2}}$

$\frac{k_{1}}{k_{2}} = \frac{t_{2}}{t_{1}}$

$t_{2} = t_{1}\frac{k_{1}}{k_{2}} = 6900 y*1.31 \cdot 10^{-11} = 9.04 \cdot 10^{-8} y*\frac{365 d}{1 y}*\frac{24 h}{1 d}*\frac{3600 s}{1 h} = 2.85 s$

Therefore, the catalyzed reaction will take 2.85 seconds to occur.

I hope it helps you!

4 0

3 years ago

Comment on whether each of the following is a homogeneous mixture or a heterogeneous mixture: (a) air in a closed bottle, (b) ai

Colt1911 [192]

Explanation:

A mixture in which there is uniform distribution of solute particles into the solvent is known as a homogeneous mixture.

For example, sugar dissolved in water is a homogeneous mixture.

On the other hand, a mixture in which there is uneven distribution of solute particles into the solvent is known as a heterogeneous mixture.

For example, sand present in water is a heterogeneous mixture.

Comment on given situations will be as follows.

(a) Air in a closed bottle - It is a homogeneous mixture because there will be even distribution of other gases that are present in air.

(b) Air over New York City - It is a heterogeneous mixture because there will be presence of some dust particles, fog or smoke into the air. Distribution of all these particles will be uneven. This will make air over New York City heterogeneous in nature.

8 0

3 years ago

Some oxides are given below. (i)Na2O (ii)NO2 (iii) CO2 (iv) MgO a) Which are the basic oxides among these? b) What is the name o

umka2103 [35]

<h3>Further explanation</h3>

Basic oxides ⇒ metal(usually alkali/alkaline earth) +O₂

L + O₂ ⇒ L₂O

L + O₂ ⇒ LO

Dissolve in water becomes = basic solution

L₂O+H₂O⇒ 2LOH

LO + H₂O⇒ L(OH)₂

So the basic oxides : Na₂O and MgO

Na₂O + H₂O⇒NaOH

MgO +H₂O⇒Mg(OH)₂

The aqueous solution of CO₂(dissolve in water)

CO₂ + +H₂O⇒ H₂CO₃(carbonic acid)

5 0

3 years ago

A student prepares a aqueous solution of butanoic acid . Calculate the fraction of butanoic acid that is in the dissociated form

ella [17]

Answer:

15.4%

Explanation:

If Ka = 0.54 mM = 1.51x10⁻⁵

Then;

C₄H₈O₂ --------> C₄H₇O₂⁻ + H⁺

I 0.54x10⁻³ 0 0

E 0.54x10⁻³(1-x) 0.54x10⁻³x 0.54x10⁻³x

Recall that x is the percentage degree of dissociation

From the ICE table;

Ka = [C₄H₇O₂⁻] [ H⁺]/[C₄H₈O₂]

1.51x10⁻⁵=(0.54x10⁻³x) (0.54x10⁻³x)/ 0.54x10⁻³(1-x)

1.51x10⁻⁵ = 0.54x10⁻³x^2/1-x

1.51x10⁻⁵(1-x) = 0.54x10⁻³x^2

1.51x10⁻⁵ - 1.51x10⁻⁵x = 0.54x10⁻³x^2

Hence;

0.54x10⁻³x^2 + 1.51x10⁻⁵x - 1.51x10⁻⁵=0

x^2 + 0.028x - 0.028 = 0

Solving the quadratic equation here;

x = 0.154 or −0.182

Ignoring the negative result, x = 0.154

Hence, fraction of butanoic acid that is in the dissociated form in this solution = 15.4%

3 0

2 years ago