Question 1

The difference in heat capacity of water versus that of air is the single greatest advantage of using water rather than air to convey heat.

Accepted Answer

Water has a much higher heat capacity than air, meaning it can absorb more heat energy for a given temperature change. This makes it a more efficient and effective medium for conveying heat.

Question 2

The quantity of heat absorbed or released from the material is expressed as Btu/hr.

Accepted Answer

The quantity of heat absorbed or released from a material is typically expressed in British Thermal Units (Btu), but without specifying a time frame such as per hour (Btu/hr), which refers to the rate of heat transfer, not the quantity of heat.

Question 3

If the material changes phase while absorbing heat, its temperature will change

Accepted Answer

When the material changes phase, it absorbs heat but its temperature remains constant until it has fully transitioned to the new phase. This is because the energy is being used to break the bonds between the molecules in the substance rather than increasing their kinetic energy (which is what causes temperature changes). Once the phase change is complete, the material's temperature will again begin to increase or decrease in response to any additional heating or cooling.

Question 4

It is often necessary to determine the quantity of heat stored in a given amount of material that undergoes a specific temperature change.An equation known as the sensible heat quantity equation, can be used for this purpose.

Accepted Answer

The statement is true, the sensible heat quantity equation is used to determine the quantity of heat stored in a material undergoing a specific temperature change.

Question 5

When hydronic systems are first filled with water, dissolved air is present in the water throughout the system.

Accepted Answer

When a hydronic system is first filled with water, dissolved air is present in the water which eventually needs to be bled out of the system.

Question 6

The specific heat of water is high in comparison to other common materials.In fact, water has one of the highest specific heats of any known material.

Accepted Answer

This statement is true. Water has a specific heat of approximately 4.18 J/g°C, which is higher than most other common materials. This means that water can absorb or release a lot of heat energy before its temperature changes significantly, making it an important regulator of temperature in many natural systems.

Question 7

When a quantity of liquid water is put under pressure, there is ____ change in its volume.&#10;A) a significant&#10;B) very little&#10;C) a corresponding&#10;D) a formulaic

Accepted Answer

When liquid water is put under pressure, its volume remains relatively unchanged. Therefore, the best choice is B: very little.

Question 8

Incompressibility implies that liquids can exert tremendous pressure in any type of filled and closed container when they ____ due to heating.&#10;A) contract&#10;B) dissolve&#10;C) expand&#10;D) vaporize

Accepted Answer

Incompressibility means that the volume of a liquid remains constant even under high pressure. Therefore, when a liquid is heated, its particles gain kinetic energy and start moving faster, resulting in an increase in volume or expansion. This expansion leads to an increase in pressure inside the container, which can be tremendous due to the inability of the liquid to compress. So, the correct answer is C) expand.

Question 9

The viscosity of a fluid is an indicator of its resistance to ____.&#10;A) flow&#10;B) heat&#10;C) combining&#10;D) displacement

Accepted Answer

Viscosity measures the resistance of a fluid to flow. It refers to the thickness or stickiness of a fluid and is affected by factors such as temperature, pressure, and molecular composition.

Question 10

The total liquid flow rate entering any portion of a fluid-filled (nonleaking) piping assembly will ____ the total flow rate exiting that assembly.&#10;A) always equal&#10;B) never equal&#10;C) might equal&#10;D) approximate

Accepted Answer

This is an application of the law of conservation of mass, which states that mass cannot be created or destroyed, only conserved. In a fluid-filled piping assembly, the mass flow rate (or volumetric flow rate, assuming the fluid is incompressible) entering the assembly must be equal to the mass flow rate exiting the assembly, as mass cannot disappear or materialize out of nowhere. Therefore, the total liquid flow rate entering any portion of such an assembly will always equal the total flow rate exiting that assembly.

Question 11

The amount of air that can exist in solution with water is strongly dependent on the water's temperature.As water is heated, its ability to hold air in solution ____.&#10;A) rapidly increases&#10;B) remains constant&#10;C) is viscosity dependent&#10;D) rapidly decreases

Accepted Answer

The answer of The amount of air that can exist...

Question 12

If the material changes phase while absorbing heat, its temperature does not change.The heat absorbed in such a process is called ____ heat.&#10;A) radiant&#10;B) sensible&#10;C) ambient&#10;D) latent

Accepted Answer

The answer of If the material changes phase while absorbing...

Question 13

The heat absorbed or released by a material while it remains in a single phase is called ____ heat.&#10;A) radiant&#10;B) sensible&#10;C) ambient&#10;D) latent

Accepted Answer

The answer of The heat absorbed or released by a...

Question 14

One of the most important properties of water relevant to its use in hydronic systems is specific heat.

Accepted Answer

The answer of One of the most important properties of...

Question 15

The vapor pressure of a liquid is the minimum pressure that must be applied at the liquid's surface to prevent it from boiling.

Accepted Answer

The answer of The vapor pressure of a liquid is...

Question 16

The density of water is not dependent on temperature.

Accepted Answer

The answer of The density of water is not dependent...

Question 17

Although it is not a defined scientific term, it could be said that water is almost ____ times more &#34;thermally concentrated&#34; than air.&#10;A) 3&#10;B) 35&#10;C) 350&#10;D) 3500

Accepted Answer

The answer of Although it is not a defined scientific...

Question 18

The rate of heat transfer into or out of the fluid stream in equations is expressed as Btu.

Accepted Answer

The answer of The rate of heat transfer into or...

Question 19

The ____ pressure of a liquid is the minimum pressure that must be applied at the liquid's surface to prevent it from boiling.&#10;A) surface&#10;B) mean&#10;C) vapor&#10;D) systemic

Accepted Answer

The answer of The ____ pressure of a liquid is...

Question 20

Hydronic system designers often need to know the ____ of heat transfer to or from a stream of water flowing through a device such as a heat source or heat emitter.&#10;A) rate&#10;B) temperature&#10;C) thermal mass&#10;D) exact volume

Accepted Answer

The answer of Hydronic system designers often need to know...

Deck 4: Properties of Water