Ch.1 Matter and Measurements
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Problem 1
Pure acetic acid, which gives the sour taste to vinegar, has a melting point of 16.7 ° C and a boiling point of 118 ° C . Predict the physical state of acetic acid when the ambient temperature is 10 ° C .Problem 21
Assuming that Coca-Cola has the same specific heat as water, how much energy in calories is removed when 350 g of Coca-Cola (about the contents of one 12 oz can) is cooled from room temperature ( 25 ° C ) to refrigerator temperature ( 3 ° C )?Problem 29
a. What is the specific gravity of the following solution?
Problem 32
Assume that you are delivering a solution sample from a pipette. Figures (a) and (b) show the volume level before and after dispensing the sample, respectively. State the liquid level (in mL) before and after dispensing the sample, and calculate the volume of the sample. a.
b.
Problem 33
Assume that identical hydrometers are placed in ethanol (sp gr 0.7893) and in chloroform (sp gr 1.4832). In which liquid will the hydrometer float higher? Explain.Problem 34
What is the difference between a physical change and a chemical change?Problem 37
Name and describe the three states of matter.Problem 38
Name two changes of state and describe what causes each to occur.Problem 40
Butane (C₄H₈) is an easily compressible gas used in cigarette lighters. It has a melting point of and a boiling point of - 138.4 degree Celsius and a boiling point of 0.5 degree Celsius. Would you expect a butane lighter to work in winter when the temperature outdoors is 25 degree F? Why or why not?Problem 42
Which of these terms, (i) mixture, (ii) solid, (iii) liquid, (iv) gas, (v) chemical element, (vi) chemical compound, applies to the following substances at room temperature? a. Gasoline b. Iodine c. Water d. Air e. Blood f. Sodium bicarbonate g. Gaseous ammonia h. SiliconProblem 43
Hydrogen peroxide, often used in solutions to cleanse cuts and scrapes, breaks down to yield water and oxygen: Hydrogen peroxide, H₂O₂ (aq) → Hydrogen, H₂ (g) + Oxygen, O₂ (g) b. Which of the substances are chemical compounds, and which are elements?Problem 54
What is the difference between a physical quantity and a number?Problem 56
Give the full name of the following units: a. cc b. dm c. mm d. nL e. mg f. m³Problem 70
Calcium citrate, Ca(C6H5O7)2(MW = 498.5 amu), is a common dietary supplement to provide calcium needed for strong teeth and bones. Look up the recommended daily dietary intake of calcium for adult men and premenopausal women.Problem 78
Obtain a package of your favorite snack food and examine the nutritional information on the label. Confirm the caloric value listed by using the conversions listed in the table in the Chemistry in Action feature 'Energy from Food' (p. 191). Alternatively, you can use the estimates for caloric value for a given food as provided in the table. How long would you have to engage in each of the physical activities to burn the calories contained in your snack?Problem 78
The white blood cell concentration in normal blood is approximately 12,000 cells/mm^2 of blood. How many white blood cells does a normal adult with 5 L of blood have? Express the answer in scientific notation.Problem 82
Calculate the specific heat of copper if it takes 23 cal (96 J) to heat a 5.0 g sample from 25 degree C to 75 degree C.Problem 83
The specific heat of fat is 0.45 cal/(g ⋅ °C) (1.9 J/g °C) and the density of fat is 0.94 g/cm^3. How much energy (in calories and joules) is needed to heat 10 cm^3 of fat from room temperature (25 degree C) to its melting point (35 degree C)?Problem 85
hen 100 cal (418 J) of heat is applied to a 125 g sample, the temperature increases by 28 degree C. Calculate the specific heat of the sample and compare your answer to the values in Table 1.10. What is the identity of the sample?Problem 93
A white solid with a melting point of 730 degree C is melted. When electricity is passed through the resultant liquid, a brown gas and a molten metal are produced. Neither the metal nor the gas can be broken down into anything simpler by chemical means. Classify each—the white solid, the molten metal, and the brown gas—as a mixture, a compound, or an element.Problem 94
Refer to the pencil in Problem 1.31. Using the equivalent values in Table 1.8 as conversion factors, convert the length measured in inches to centimeters. Compare the calculated length in centimeters to the length in centimeters measured using the metric ruler. How do the two values compare? Explain any differences.
Problem 95
Gemstones are weighed in carats, where 1 carat = 200 mg exactly. What is the mass in grams of the Hope diamond, the world's largest blue diamond, at 44.4 carats?Problem 103
Today, thermometers containing mercury are used less frequently than in the past because of concerns regarding the toxicity of mercury and because of its relatively high melting point (-39 degree C). This means that mercury thermometers cannot be used in very cold environments because the mercury is a solid under such conditions. Alcohol thermometers, however, can be used over a temperature range from - 115 degree C (the melting point of alcohol) to 78.5 degree C (the boiling point of alcohol). b. The densities of alcohol and mercury are 0.79 g/mL and 13.6 g/mL, respectively. If the volume of liquid in a typical laboratory thermometer is 1.0 mL, what mass of alcohol is contained in the thermometer? What mass of mercury?Problem 108
When 1.0 tablespoon of butter is burned or used by our body, it releases 100 kcal (100 food Calories or 418. 4 kJ) of energy. If we could use all the energy provided, how many tablespoons of butter would have to be burned to raise the temperature of 3.00 L of water from 18.0 ℃ to 90.0 ℃Problem 109
An archeologist finds a 1.62 kg goblet that she believes to be made of pure gold. When 1350 cal (5650 J) of heat is added to the goblet, its temperature increases by 7.8 ℃. Calculate the specific heat of the goblet. Is it made of gold? Explain.
