Matter and Energy

Identify each of the following changes of state as evaporation, boiling, or condensation:

a. At ${100}^{\circ }C$ the water in at pan changes to steam.

b. On a cool morning, the windows in your car fog up.

C. A shallow pond dries up in the summer.

d. Your teakettle whistles when the water is ready for tea.

Identify each of the following changes of state as evaporation. boiling, or condensation:

a. The water vapor in the clouds changes to rain.

b. Wet clothes dry on a clothesline.

c. Lava flows into the ocean and steam forms.

d. After a hot shower, your bathroom mirror is covered with water.

a. During one week, Charles swam for a total of 2.5h and walked for a total of 8h. If Charles expends 340kcal/h swimming and 160kcal/h walking, how many total kilocalories did he expend for one week?

b. For the amount of exercise that Charles did for one week in part a, if expending 3500 kcal is equal to a loss of 1.0 lb, how many pounds did he lose?

c. How many hours would Charles have to walk to lose 1.0 lb?

d. How many hours would Charles have to swim to lose 1.0 lb?

Using energy values from Table 3.8, determine each of the following:

a. the total kilocalories for each meal

b. the total kilocalories for one day

c. If Charles consumes 1800 kcal per day, he will maintain his weight. Would he lose weight on his new diet?

d. If expending 3500 kcal is equal to a loss of 1.0 lb, how many days will it take Charles to lose 5.0 lb?

Using the values for the heat of fusion, specific heat of water, and/or heat of vaporization, calculate the amount of heat energy in each of the following:

a. joules needed to melt $50.0 g$ of ice at $0^{\circ }C$ and to warm the liquid to ${65}^{\circ }C$

b. Kilocalories released when $15.0 g$ of steam condenses at ${100}^{\circ }C$ and the liquid cools to $0^{\circ }C$

C. kilojoules needed to melt $24.0 g$ of ice at $0^{\circ }C$, warm the liquid to ${100}^{\circ }C$, and change it to steam at ${100}^{\circ }C$.

A sports trainer applies an ice bag to the back of an injured athlete. Calculate the beat, in kilocalories, that is absorbed if $145 g$ of ice at $0.0^{\circ }C$ is placed in an ice bag, melts, and warms to body temperature of $37.0^{\circ }C$.

A patient arrives in the emergency room with a burn caused by steam, Calculate the heat, in kilocalories, that is released when $18.0 g$ of steam at ${100}^{\circ }C$ hits the skin, condenses, and cools to body temperature of $37.0^{\circ }C$.

Draw a heating curve for a sample of ice that is heated from $-{20}^{\circ }C$ to ${150}^{\circ }C$. Indicate the segment of the graph that corresponds to each of the following:

a. solid

b. melting

c. liquid

d. boiling

c. gas

Using the values for the heat of fusion, specific heat of water. and/or heat of vaporization, calculate the amount of heat energy in each of the following:

a. joules released when $125 g$ of steam at ${100}^{\circ }C$ condenses and cools to liquid at $15.0^{\circ }C$ 

b. kilocalories needed to melt a $525-g$ ice sculpture at $0^{\circ }C$ and to warm the liquid to $15.0^{\circ }C$ 

c. kilojoules released when $85.0 g$ of steam condenses at ${100}^{\circ }C$, cools, and freezes at $0^{\circ }C$

Calculate the heat change at ${100}^{\circ }C$ for each of the following. and indicate whether heat was absorbed/released:

a. calories to condense $10.0 g$ of steam

b. joules to condense $7.60 g$ of steam

E. Kilocalories to vaporize $44 g$ of water

d. kilojoules to vaporize $5.00 Kg$ of water

Identify each of the following as an element, a compound, or a mixture. Explain your choice. (3.1)

Calculate the energy to heat two cubes (gold and aluminium) each with a volume of $10c{m}^3$ from ${15}^{o}C$ to ${25}^{o}C$. Refer to Tables 2.8 and 3.11. (3.6)

Identify each of the following as an element, a compound, or a mixture. Explain your choice. (3.1)

Classify each of the following as a homogeneous or heterogeneous mixture: 

a. lemon-flavored water

b. stuffed mushrooms

c. eye drops

Identify each of the following as a homogeneous or heterogeneous mixture. Explain your choice.$(3.1)$

State the temperature on the Celsius thermometer and convert to Fahrenheit. (3.3)

State the temperature on the Celsius thermometer and convert to Fahrenheit. $(3.3)$

After a week, biochemical reactions in compost slow, and the temperature drops to $45°C.$ The dark brown organic-rich mixture is ready for use in the garden. What is this temperature in degrees Fahrenheit? In kelvins?$(3.3)$

Classify each of the following as a homogeneous or heterogeneous mixture: $(3.1)$

Compost can be made at home from grass clippings, kitchen scraps, and dry leaves. As microbes break down organic matter, heat is generated and the compost can reach a temperature of $155°F$, which kills most pathogens. What is this temperature in degrees Celsius? In kelvins? (3.3)

Compost produced from decayed plant material is used to enrich the soil.

Calculate the energy to heat two cubes (silver and copper), each with a volume of $10c{m}^3$from ${15}^{\circ }\mathrm{C}\text{ to }{25}^{\circ }\mathrm{C}$.

A$70.0$-kg person had a quarter-pound cheeseburger, french fries, and a chocolate shake. $\left(3.5\right)$

a. Using Table $3.7$, calculate the total kilocalories for each food type in this meal (round off the kilocalories to the tens place).

b. Determine the total kilocalories for the meal (round off to the tens place).

c. Using Table $3.10$, determine the number of hours of sleep needed to burn off the kilocalories in this meal.

d. Using Table $3.10$, determine the number of hours of running needed to burn off the kilocalories in this meal.

Identify each of the following as a physical or chemical property: (3.2)

a. Gold is shiny.

b. Gold melts at $1064°\mathrm{C}$

c. Gold is a good conductor of electricity,

d. When gold reacts with sulfur, a black sulfide compound forms.

Your friend, who has a mass of $70.0kg$, has a slice of pizza, a cola soft drink, and ice cream. $\left(3.5\right)$

a. Using Table, calculate the total kilocalories for each food type in this meal (round off the kilocalories to the tens place).

b. Determine the total kilocalories for the meal (round off to the tens place).

c. Using Table, determine the number of hours of sitting needed to burn off the kilocalories in this meal.

d. Using Table, determine the number of hours of swimming needed to burn off the kilocalories in this meal.

Identify each of the following as a physical or chemical property: (3.2)

a.$A$ candle is 10 in. high and 2 in. in diameter.

b. A candle burns.

c. The wax of a candle softens on a hot day.

d. A candle is blue.

Identify each of the following as a physical or chemical change: $(3,2)$

a. A plant grows a new leaf.

b. Chocolate is melted for a dessert.

c. Wood is chopped for the fireplace.

d. Wood barns in a woodstove.

Classify each of the following as an element, a compound, or a mixture; $\left(3.1\right)$

a. carbon in pencils

h. carbon monoxide (CO) in automobile exhaust

c. orange juice

Classify each of the following as an element, a compound, or a mixture; $\left(3.1\right)$

a. neon gas in lights

b. a salad dressing of on and vinegar

c. sodium hypochlorite (NaCIO) in bleach

Classify each of the following mixtures as homogeneous of heterogeneous: $\left(3.1\right)$

a. hot fudge sundae

b. herbal tea

c. vegetable oil

Classify each of the following mixtures as homogeneous or heterogeneous: $\left(3.1\right)$

al. Water and sand

b. mustard

c. blue ink

Identify each of the following as solid, liquid, or gas: $\left(3.2\right)$

a. vitamin tablets in a bottle

b. helium in a balloon

c. milk in a bottle

d. the air you breathe

e. charcoal briquettes on a barbecue

Identify each of the following as solid., liquid, of gas: $\left(3.2\right)$

a. popcorn ant a bag

b. water in a garden hose

c. a computer mouse

d. air in a tire

e. hot tea in a teacup

Identify each of the following as a physical or chemical change: $(3,2)$

a. Aspirin tablets are broken in half.

b. Carrots are grated for use in a salad.

c. Mall undergoes fermentation to make beer.

d. A copper pipe reacts with air and turns green.

Calculate each of the following temperatures in degrees Celsius and kelvins: (3.3)

a. The highest recorded temperature in the continental United States was $134°\mathrm{F}$in Death Valley, California, on July 10, $1913$

b. The lowest recorded temperature in the continental United States was $-69.7°\mathrm{F}$ in Rodgers Pass, Montana, on January $20,1954$

Calculate each of the following temperatures in kelvins and degrees Fahrenheit: $(3.3)$

a. The highest recorded temperature in the world was $58.0{}^{\circ }\mathrm{C}$in El Azizia, Libya, on September 13, 1922.

b. The lowest recorded temperature in the world was$-89.2{}^{\circ }\mathrm{C}$in Vostok, Antarctica, on July 21, 1983.

What is $-15°\mathrm{F}$ in degrees Celsius and in keivins? $(3.3)$

A 0.50-g sample of vegetable off is placed in a calorimeter. When the sample is burned, $18.9 \mathrm{kJ}$is given off. What is 4 energy value (kcal/g) for the oil? (3.5)

The melting point of dibromomethane is $-{53}^{o}C$ and its boiling point is ${97}^{o}C$. Sketch a heating curve for dibromomethane from $-{100}^{\circ }\mathrm{C}\text{ to }{120}^{\circ }\mathrm{C}$.

a. What is the state of dibromomethane at $-{75}^{\circ }\mathrm{C}$?

b. What happens on the curve at $-{53}^{\circ }\mathrm{C}$ ?

c. What is the state of dibromomethane at $-{18}^{\circ }\mathrm{C}$ ?

d. What is the state of dibromomethane at ${110}^{o}C$ ?

e. At what temperature will both solid and liquid be present? 

 What is $-{15}^{\circ }\mathrm{F}$ in degrees Celsius and in kelvins? 

What is ${56}^{\circ }\mathrm{F}$ in degrees Celsius and in kelvins?

A 0.50-g sample of vegetable oil is placed in a calorimeter. When the sample is burned, 18.9 KJ is given off. What is the energy value (kcal/g) for the oil? 

On a hot day, the beach sand gets hot but the water stays cool. Would you predict that the specific heat of sand is higher or lower than that of water? Explain. 

On a hot sunny day, you get out of the swimming pool and sit in a metal chair, which is very hot. Would you predict that the specific heat of the metal is higher or lower than that of water? Explain. 

A $1.3-\mathrm{g}$ sample of rice is placed in a calorimeter. When the sample is burned, $22\mathrm{kJ}$ is given off. What is the energy value $(\mathrm{kcal}/\mathrm{g})$ for the rice? 

The following graph is a heating curve for chloroform, a solvent for fats, oils, and waxes: ($3.7$)

a. What is the approximate melting point of chloroform?

b. What is the approximate boiling point of chloroform?

c. On the heating curve, identify the segments $A$, $B$, $C$, $D$, and $E$ as solid, liquid, gas, melting, or boiling.

d. At the following temperatures, is chloroform a solid, liquid, or gas?

$-{80}^{\circ }\mathrm{C};-{40}^{\circ }\mathrm{C};{25}^{\circ }\mathrm{C};{80}^{\circ }\mathrm{C}$

Associate the contents of the beakers ( $1$ to $5$ ) with segments ($A$ to $E$ ) on the following heating curve for water: ($3.7$)

A young patient drinks whole milk as part of her diet. Calculate the total kilocalories if the glass of milk contains $12g$ of carbohydrate, $9g$ of fat, and $9g$ of protein. (Round off answers for each food type to the tens place.) $\left(3.5\right)$

A hot-water bottle for a patient contains $725 g$ of water at ${65}^{\circ }C$. If the water cools to body temperature $\left({37}^{\circ }C\right)$, how many kilojoules of heat could be transferred to sore muscles? 

The highest recorded body temperature that a person has survived is $46.5^{\circ }C$. Calculate that temperature in degrees Fahrenheit and in kelvins. 

 On a hot day, the beach sand gets hot but the water stays cool. Would you predict that the specific hent of sand is higher or lower than that of water? Explain.