Question

In: Mechanical Engineering

Indicate whether the following statements are true or false. Explain. The specific enthalpy of an ideal...

Indicate whether the following statements are true or false. Explain.

The specific enthalpy of an ideal gas is a function of temperature and pressure.
Air cannot be regarded as a pure substance.
Liquid alternatively referred to as compressed liquid because its pressure is less than atmospheric pressure.
The pressure and temperature are not dependently variable for a system contains a two-phase liquid–vapor mixture at equilibrium.

Expert Solution

1). The specific enthalpy of an ideal gas is a function of temperature and pressure.

-False

The specific enthalpy of an idea gas is a function of temperature only.

As we know that idea gas follows the equation PV =nRT, that means product of pressure and volume(work) is a function of temperature only since R and n are constants.

We also know that internal energy is a function of temperature i.e u(t)

Now enthalpy h = u + Pv

This proves that enthalpy of an ideal gas is function of temperature only as u and Pv are also function of temperature only.

2). Air cannot be regarded as a pure substance.

- True, air cannot be regarded as a pure substance.

Pure substances are the one which are made up of only one kind of material, For e.g iron is a pure substance as it contains only iron molecules. As we no that air comprises of different gases like Oxygen, Nitrogen, Carbon dioxide etc. This gases are different altogether, thus air is not a pure substance.

3). Liquid alternatively referred to as compressed liquid because its pressure is less than atmospheric pressure.

False,

A liquid remains compressed when its pressure is above its saturation pressure(P_s). Once the pressure is reduced than atmospheric pressure, the liquid tends to boil earlier. (Considering temperature to be constant). Saturation pressure is the one at which the liqud starts boiling. There is a particular saturation pressure for each value of temperature.

For e.g at 99.97 degree celsius, saturation pressure is 1 atm (For water). If we increase pressure than 1atm, the liquid can be considered to be compressed. However if we decrease the pressure of liquid than 1 atm, It will no longer remain compressed and start to boil.

4). The pressure and temperature are not dependently variable for a system contains a two-phase liquid–vapor mixture at equilibrium.

False,

For a two phase mixture, pressure and temperature are dependent on each other. For e.g, considering example of wet steam(Water + Steam), At 1 atm pressure, the temperature of liquid-vapor mixture is 99.97 degree Celsius.

But for the same mixture present at 2 atm, the temperature at which the liquid vapor matter(wet steam) will come into existence is 120.628 degree celsius. Thus pressure and temperature are interdependent.

samet mamat answered 2 years ago

Indicate whether the following statements are (True) or (False) and correct the False statements:

Indicate whether the following statements are (True) or (False) and correct the False statements: 1. The corporate treasurer typically handles both cost accounting and financial accounting. 2. Marginal analysis states that financial decisions should be made and actions taken only when added benefits are greater than zero. ( 3. The conflict between the goal of a firm's owners and the goal of its non-owner managers is incompatibility. () 4. The sale of either bonds or stocks to the general public is called private placement....

Indicate whether the following statements are true or false, and then explain your answers: a. The...

Indicate whether the following statements are true or false, and then explain your answers: a. The marginal revenue from selling another unit of eggs can never be higher than the price of eggs. b. Because the price a seller charges is always greater than $0, the marginal revenue from selling another unit must also be greater than $0. 17. Consider the market for Pop Rocks depicted in the diagram below: a. If the Pop Rock industry were competitive, what would...

Indicate whether each of the following statements is true or false. If false, indicate how to...

Indicate whether each of the following statements is true or false. If false, indicate how to correct the statement. a. The amount reported for accumulated other comprehensive income (AOCI) on the balance sheet must be a positive amount consistent with all other stockholders’ equity accounts. b. Changes in AOCI are reflected in other comprehensive income, which is different from net income. c. Other comprehensive income does not imply a change in cash.

Indicate whether each of the following statements is true or false, and explain why. A competitive...

Indicate whether each of the following statements is true or false, and explain why. A competitive firm that is incurring a loss should immediately cease operations. A pure monopoly does not have to worry about suffering losses because it has the power to set its prices at any level it desires. In the long run, firms operating in perfect competition and monopolistic competition will tend to earn normal profits. Assuming a linear demand curve, a firm that wants to maximize...

Indicate whether the following statements are true, false, oruncertain. Explain why. (a) As income is...

Indicate whether the following statements are true, false, or uncertain. Explain why. (a) As income is eventually spent on consumption, income and consumption taxes are equivalent. (b) If we use wage rate as basis of taxation, it satisÖes horizontal equity. (c) By increasing corporation income tax rate, we can reduce income inequality. (d) We can eradicate the underground economy by imposing heavy tax. (e) Progressive income tax scheme is necessarily involved with increasing marginal tax rate. (f) If we collect...

Indicate whether the following statements are TRUE or FALSE and explain your answer fully with an...

Indicate whether the following statements are TRUE or FALSE and explain your answer fully with an adequate explanation a)An efficient outcome is desirable because it allows us to make Pareto improvements. b)Unlike a consumer, a firm does not face a budget constraint. c)If the wage rate increases, then those who work have a stronger incentive to supply labor.

Indicate whether the following statements are true, false, or uncertain. Explain why. (a) As income is...

Indicate whether the following statements are true, false, or uncertain. Explain why. (a) As income is eventually spent on consumption, income and consumption taxes are equiv- alent. (b) If we use wage rate as basis of taxation, it satisÖes horizontal equity. (c) By increasing corporation income tax rate, we can reduce income inequality. (d) We can eradicate the underground economy by imposing heavy tax. (e) Progressive income tax scheme is necessarily involved with increasing marginal tax rate. (f) If we...

Indicate whether each of the following statements is true or false. If it is false, you...

Indicate whether each of the following statements is true or false. If it is false, you must explain why it is false (you can use equations as part of an explanation when needed). Not explaining is the same thing as not answering. If it is true, no explanation is needed: a. The Romer model is useful because it allows us to explain why poorer countries grow faster than richer countries. b. The main difference between the Solow model and the...

Indicate whether the following statements are always true or can be false. True False If an object's...

Indicate whether the following statements are always true or can be false. True False If an object's speed does not change, no net force is acting on the object. True False If two objects are under the influence of equal forces, they have the same acceleration. True False The net force which acts on an object which maintains a constant velocity is zero. True False An object's velocity will change if a net force acts on the object. True False A truck initially moving at...

Indicate whether the following statements are true or false - Increasing the number...

Indicate whether the following statements are true or false - Increasing the number of units in a batch increases batch-level costs - Eliminating a business segment often allows a company to avoid some facility-level costs - To analyze a special order decision, a manager should identify differential costs and revenues. - Reliability of the supplier is a critical issue in an outsourcing decision. - Availability of...