1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Bad White [126]
3 years ago
7

Consider a bathtub holding a system of water (where the boundaries of the tub are the boundaries of the system) under the follow

ing conditions:
(a) The bathtub has a closed drain and is already full of water at the start of analysis. No steam rises from the water. You want to examine heat transfer loss from the water contained in the tub over time.
(b) The bath tub drain is partially open and hot water is continually added to keep the tub filled and the temperature constant. You want to examine the flow rates required to maintain the temperature of the water in the tub.
For each system (a) and (b), determine if it is characterized as open or closed and state your reasoning.
Chemistry
1 answer:
Luba_88 [7]3 years ago
4 0

Answer:

a)  the system is closed

b) the system is open

Explanation:

a) the system can be characterised as closed system. If we define the boundaries of this system as an envelope that contains the bathtub, then there will not be any mass transfer to the environment through the boundary → then the system is closed ( the mass of the system remains constant)

b) on the other hand , taking the same system as in the first case, if the hot water is continually added to the tub , then there is water flow through the boundary (from the environment to the system) → then the system is open ( the mass of the system can be altered)

You might be interested in
Which of the following pairs of elements would most likely combine to form a salt?
Delvig [45]
B.sodium and aluminum
4 0
3 years ago
Consider the following reaction: A(g)⇌2B(g). Find the equilibrium partial pressures of A and B for each of the following differe
Illusion [34]

Answer:

a. Kp=1.4

P_{A}=0.2215 atm

P_{B}=0.556 atm

b.Kp=2.0 * 10^-4

P_{A}=0.495atm

P_{B}=0.00995 atm

c.Kp=2.0 * 10^5

P_{A}=5*10^{-6}atm

P_{B}=0.9999 atm

Explanation:

For the reaction  

A(g)⇌2B(g)

Kp is defined as:

Kp=\frac{(P_{B})^{2}}{P_{A}}

The conditions in the system are:

          A                    B

initial   0                1 atm

equilibrium x       1atm-2x

At the beginning, we don’t have any A in the system, so B starts to react to produce A until the system reaches the equilibrium producing x amount of A. From the stoichiometric relationship in the reaction we get that to produce x amount of A we need to 2x amount of B so in the equilibrium we will have 1 atm – 2x of B, as it is showed in the table.    

Replacing these values in the expression for Kp we get:

Kp=\frac{(1-2x)^{2}}{x}

Working with this equation:

x*Kp=(1-2x)^{2} - -> x*Kp=4x^{2}-4x+1- - >4x^{2}-(4+Kp)*x+1=0

This last expression is quadratic expression with a=4, b=-(4+Kp) and c=1

The general expression to solve these kinds of equations is:

x=\frac{-b(+-)*\sqrt{(b^{2}-4ac)}}{2a} (equation 1)

We just take the positive values from the solution since negative partial pressures don´t make physical sense.

Kp = 1.4

x_{1}=\frac{(1.4+4)+\sqrt{(-(1.4+4)^{2}-4*4*1)}}{2*4}=1.128

x_{1}=\frac{(1.4+4)-\sqrt{(-(1.4+4)^{2}-4*4*1)}}{2*4}=0.2215

With x1 we get a partial pressure of:

P_{A}=1.128 atm

P_{B}=1-2*1.128 = -1.256 atm

Since negative partial pressure don´t make physical sense x1 is not the solution for the system.

With x2 we get:

P_{A}=0.2215 atm

P_{B}=1-2*0.2215 = 0.556 atm

These partial pressures make sense so x2 is the solution for the equation.

We follow the same analysis for the other values of Kp.

Kp=2*10^-4

X1=0.505

X2=0.495

With x1

P_{A}=0.505atm

P_{B}=1-2*0.505 = -0.01005 atm

Not sense.

With x2

P_{A}=0.495atm

P_{B}=1-2*0.495 = 0.00995 atm

X2 is the solution for this equation.  

Kp=2*10^5

X1=50001

X2=5*10^{-6}

With x1

P_{A}=50001atm

P_{B}=1-2*50001=-100001atm

Not sense.

With x2

P_{A}= 5*10^{-6}atm

P_{B}=1-2*5*10^{-6}= 0.9999 atm

X2 is the solution for this equation.  

8 0
4 years ago
A sample of the chiral molecule limonene is 62% enantiopure. what percentage of each enantiomer is present? what is the percent
ikadub [295]

The mixture contains 62 % one isomer and 38 % the enantiomer.

Let’s say that the mixture contains 62 % of the (<em>R</em>)-isomer.

Then % (<em>S</em>) = 100 % -62 % = 38 %

ee = %  (<em>R</em>) - % (<em>S</em>) = 62 % -38 % = 24 %


6 0
3 years ago
Read 2 more answers
In an endothermic reaction what is true of the enthalpy
charle [14.2K]

Answer is: a) is has increased.

There are two types of reaction:  

1) endothermic reaction (chemical reaction that absorbs more energy than it releases).

For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).  

For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.

4 0
4 years ago
A train that is accelerating at 5m/s² down the tracks and crashes into a car. If the train weighs 20,000kg, how much force does
iragen [17]

Answer:

100,000 N

Explanation:

Force, F = mass, m × acceleration, a

⇒F = ma

m= 20, 000kg

a = 5m/s²

∴ F = 5 × 20,000 = 100,000N

3 0
3 years ago
Other questions:
  • How could you use two beakers distilled water two hot plates two thermometers and salt to test if adding salt affects the boilin
    8·1 answer
  • What is the density of a sample of liquid that has a volume of 125 mL and a mass of 200 g?
    9·1 answer
  • Which correctly defines a basic solution?
    11·2 answers
  • Butter has a specific gravity of 0.86. What is the mass of 2.15 L of butter?
    12·1 answer
  • In any chemical compound , the elements are always combined in the same proportion by
    11·1 answer
  • ___is a self improvement strategy for a busy person who has difficulty finding time to exercise
    11·1 answer
  • Написати 4 пункта +до кожного приклад
    8·1 answer
  • All acid base indicators ____
    9·1 answer
  • Plsssss help !! what are the steps to convert from atoms, compounds, formula units, ect to moles
    14·1 answer
  • HURYY!! Karst topography can cause drinking water to become:
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!