ch. 17 physics

Steam burns are more damaging than burns caused by boiling water because steam

) has more energy per gram than boiling water. B) releases additional energy when it condenses. C) both of these

The minimum amount of steam at 100°C needed to melt 1 gram of 0°C ice is

0.125g

Which will melt more ice when placed on its surface, a kilogram of wood or a kilogram of iron of the same high temperature?

1 kg of wood

To increase the temperature of 50 grams of water by 2 Celsius degrees requires

100 calories

A boy scout will be burned more severely by

100 g of steam at 100°C

The calories needed to change 10 grams of ice at 0°C to steam at 100°C is

7200

The mass of ice that can be melted by 1 gram of 100°C steam is (Hint: Don't forget about hot water remaining from condensed steam.)

8 g

The toy drinking bird nicely illustrates

A) evaporation. B) condensation

In a heat pump, warming is accomplished when

Condensation occurs in its coils

When water freezes, the surrounding air is

Warmed

The molecules in a room-temperature glass of water jostle around at

a great variety of speeds

Compared to sea level, water in an open pot in the mountains boils at

a lower temperature

Evaporation is a cooling process and condensation is

a warming process

When a solid melts, energy is

absorbed by the solid

When vapor transforms to a plasma, energy must be

absorbed by the vapor

When a solid is changed to a liquid, the solid

absorbs energy

The main difference between a fog and a cloud is

altitude

Water can be brought to a boil by

applying heat and reducing air pressure on its surface

A heat pump can

both of these

Ice is put in a cooler to cool the contents. To speed up the cooling process, the ice can be

broken into smaller pieces

A geyser such as Old Faithful in Yellowstone Park is similar to a

coffee percolator

When condensation occurs inside your bedroom window, the air outside is appreciably

colder

Double-pane windows contain nitrogen rather than air to prevent

condensation

We feel uncomfortably warm on a muggy day because water molecules are

condensing on our bodies

When you blow over hot soup to cool it you are helping

conduction, convection, and radiation

Melting snow tends to

cool the surrounding air

A canteen that is wet on the outside results in water inside that is

cooler

When a geyser erupts, pressure at its bottom

decreases

To melt ice, add

energy

The surface of hot water has a relatively high rate of

evaporation

Wrapping a hot potato in aluminum foil significantly reduces the rate at which it cools by

evaporation

What occurs in a pan of water placed outdoors on a warm day?

evaporation, condensation

Compared with sea-level cooking, in cooking eggs by boiling in mountain regions you should boil the eggs

for a longer time

Rapid evaporation of hot water can lead to

formation of ice

The addition of salt to water affects its

freezing point

Hydrothermal vents deep beneath the ocean surface attain temperatures far above 100°C due to

greater pressure

The pressure at the bottom of a geyser is

greater than nearer the top

Food in a pressure cooker is cooked faster due to

higher temperature

The temperature at which water freezes is the same as the temperature at which

ice melts

You can add heat without raising temperature to

ice. B) boiling water

Stored potatoes, beets, and rutabagas in an unheated well-insulated room can be protected from freezing by having in the room

large tubs of water

Foreign ions introduced to water

lower the freezing point of water

Water can be turned to ice by

lowering the surrounding air pressure. B) extracting energy

To turn 1 gram of boiling water to steam requires

more energy than needed to turn 1 gram of absolute-zero ice to the boiling point

To turn 50 grams of boiling water to steam requires

more than 540 calories

In mountain regions, food cooked in boiling water cooks slower than when cooked at sea level. If the temperature beneath the pot of boiling water is increased, the food will cook

neither

When you walk barefoot on red-hot wooden coals it is best if

no pieces of metal are among the coals

To melt 50 grams of 0-degree-Celsius ice requires

none of the above

Dean teaches that the phenomenon of regelation is due to the

open-structured nature of ice crystals

In one word, how can water in the power plant of a nuclear submarine far exceed 100°C?

pressure

Increased air pressure on the surface of hot water tends to

prevent boiling

An inventor discovers a harmless and tasteless salt, which when added to water changes its boiling point. The market value for this salt will be better if the salt

raises the boiling point of water

When fast-moving water molecules collide they tend to

rebound without sticking

Water in a car radiator sometimes boils explosively when the radiator cap is removed, which is due to sudden

reduced pressure

When liquids change to a solids, they

release energy

When moth balls sublime to gas they

release energy

When a vapor condenses, energy is

released from the vapor

When a gas is changed to a liquid, the gas

releases energy

When heat is added to boiling water, its temperature

remains unchanged

For increased atmospheric pressure, the boiling point of water

rises

Morning dew on the grass is a result of

slow-moving water molecules sticking to one another.

Firefighters find that the temperature of burning material is best lowered when water

sprayed as a fine mist

When slow-moving water molecules collide they tend to

stick

The most responsible factor for whether a substance takes the phase of solid, liquid, gas, or plasma is its

temperature

Which involves a larger number of calories?

the condensation of 1 gram of steam at 100°C to water at 100°C

The reason that evaporation is a cooling process is

the more energetic molecules escape the liquid

A good cook knows that the temperature of violently boiling water is

the same as that of simmering water

The temperature at which a liquid freezes is

the same temperature at which its solid form melts

Stored potatoes, beets, and rutabagas freeze at temperatures below zero degrees Celsius (rather than at exactly zero) because

the water in them contains dissolved salts and sugars

A hot dog pants

to enable evaporation in its mouth and bronchial tract

On a muggy day, water molecules in the air that strike our bodies

transfer some of their kinetic energy to us

A refrigerator

transfers internal energy from inside to outside

In a heat pump, cooling is accomplished when

vaporization occurs in its coils

The cooling effect inside a refrigerator is produced by

vaporizing the refrigeration liquid

During snow fall, the surrounding air is

warmed

When steam condenses, the surrounding air is

warmed

When water vapor changes phase to become water in a cloud, the surroundings become

warmer

When water vapor condenses on the inside of a window, the room becomes slightly

warmer

When ice crystals form in clouds, the surrounding air

warms

If bits of the coals do not stick to your feet while walking barefoot on red-hot coals, it would be best if your feet are

wet

To illustrate regelation with ice it is important that a

wire is used

As a block of ice at 0°C melts, the block absorbs energy

without a temperature change