Chem 121 Exam 1

What is the meaning of the metric prefix "micro-"? A. 10^-6 B. 10^-9 C. 10^3 D. 10^6 E. 10^-2

A. 10^-6

What is the mass of a sample of lead that has a density of 11.4 g/mL and displaces 20.1 mL of water? A. 229 g B. 0.567 g C. 1.76 g D. 11.4 g E. 2.30 × 10-2 g

A. 229 g 20.1ml x (11.4g/1ml) = 229g

How many joules are required to raise the temperature of 1.074 g of iron from 25.1 °C to 100.0 °C? (The specific heat of iron is 0.449 J/g • °C) A. 36.1 J B. -36.1 J C. 0.036 J D. -0.036 J E. 0.449 J

A. 36.1 J q=mCΔT = (1.074 g) x (0.449 J/g°C) x (100.0-25.1°C) = 36.1 J ΔT = final - initial Raising temperature so system is GAINING energy so it's endothemic and q is positive value

Which digit(s) is/are certain in the measurement of 98.6 °F? A. 98 B. 98.6 C. 6 D. 8 E. 9

A. 98 (last digit is uncertain in measured data)

Which of the following is NOT a chemical property? A. The density of a liquid B. The ability of iron to rust C. Flammability of gasoline D. Reactivity of acids with metals E. All of these are chemical properties.

A. The density of a liquid

What are the two important parts of ameasurement? A. The number and the unit B. The number and the exponent C. The number and the decimal D. The decimal and exponent

A. The number and the unit

Which of the following is a pure substance? A. Sodium B. Milk C. Blood D. Saline solution E. Stainless steel

A. sodium Element and compounds are pure substances and sodium is an element!

How many cubic feet are in 1.2 yd^3? A. 3.6 ft^3 B. 32 ft^3 C. 0.40 ft^3 D. 2.4 ft^3 E. None of the above

B. 32 ft^3 1.2yd^3 x (27ft^3/1yd^3)

Convert 97 °C to K and express the answer to the correct number of significant figures. A. 369 K B. 370 K C. 397 K D. -176 K E. No answer listedis correct.

B. 370 K K = 97 + 273.15 = 370 K (round to one's place)

What is the result of the following problem expressed with the correct number of significant figures? A. 9.6 B. 9.58 C. 9.581 D. 30.72 E. 10.

B. 9.58 9.581 = 9.58 Least accurate decimal location for + and - sig fig rule

Which of the following statements is FALSE? A. The freezing of water is a physical change. B. The conversion of compounds into elements is a physical change. C. Combining sodium metal and chlorine gas to form sodium chloride is a chemical change. D. Photosynthesis is an example of a chemical change. E. Distilling alcohol from water is a physical change.

B. The conversion of compounds into elements is a physical change.

Using the following information, indicate which of the choices below is correct: The temperature of iron increases more quickly than water when it is heated. A. Iron has a greater heat capacity than water. B. Water has a greater heat capacity than iron. C. Iron and water have the same heat capacity. D. The boiling point of water is greater than that of iron. E. None of the above.

B. Water has a greater heat capacity than iron.

Matter can be defined as... A. a substance that cannot be broken down any further. B. anything that has mass and occupies space. C. a substance composed of two or more elements. D. a homogeneous mixture. E. None of the above

B. anything that has mass and occupies space.

What is the metric prefix for the factor 10^-9? A. centi- B. nano- C. pico- D. milli- E. micro-

B. nano-

How many feet are in 0.4734 km? A. 1.55 × 102 ft B. 5.681 ft C. 1.5531 × 103 ft D. 0.155 ft E. 1553 ft

C. 1.5531 × 103 ft 0.4734km x (0.6214mi/1km) x (5280ft/1mi)

How many kJ of energy are in a fast food hamburger containing 560. Calories? (Note: 1 cal = 4.184 J) A. 2.34 kJ B. 5.60 kJ C. 2.34 x 103 kJ D. 2.34 x 106 kJ E. 5.60 x 103 kJ

C. 2.34 x 103 kJ Cal cal J kJ 560 Cal x 1000 cal/1 Cal x (4.184 J/1 cal) x 1 kJ/1000 J =(560 x 1000 x 4.184) / 1000 = 2.34 x 103 kJ

The gas mileage of a compact car in Europe is 15 km/L. How many miles per gallon would this vehicle obtain in the U.S.?(Note: 1 U.S. gal = 3.785 L; 1 km = 0.6214 mi.) A. 15 mi/gal B. 30. mi/gal C. 35 mi/gal D. 42 mi/gal E. 55 mi/gal

C. 35 mi/gal (15km/L) x (0.6214mi/1km) x (3.785L/1gal) = 35 mi/gal

The number 5.43 × 10-6 L can also be written as... A. 5.43 kL. B. 5.43 mL. C. 5.43 µL. D. 5.43 nL. E. 5.43 pL.

C. 5.43 µL. 1 μl = 10-6 L

What is the volume in liters of 54.50 g of a liquid with a density of 0.9502 g/mL? A. 57.36 L B. 0.0574 L C. 5.736 × 10-2 L D. 0.574 L E. 573.6 L

C. 5.736 × 10-2 L 54.50g x (1ml/0.9502g) x (1L/1000ml)

How many significant figures are in 0.00500670? A. 3 B. 5 C. 6 D. 8 E. 9

C. 6 0.00 500670

When a sample of wood is burned, the mass of the reactants is 100. grams. If 15.0 g of ash is one product, what is the mass of the other products? A. 115 g B. 100. g C. 85 g D. 15.0 g E. 1.0 g

C. 85 g Mass Reactant = Mass Product Mass = 100 grams 100-15 = 85

The state of matter in which molecules are widely spaced is... A. a solid. B. a liquid. C. a gas. D. elemental. E. molecular.

C. a gas

A solution is a(n)... A. element. B. compound. C. homogenous mixture. D. heterogeneous mixture. E. pure substance.

C. homogenous mixture.

While driving in Australia, you fill your car with 55.0 L of gas costing $44.55 (Australian). What is the equivalent cost per gallon in U.S. dollars? (Note: 1 gal = 3.785 L; $1 Australian = $0.7597 U.S.) A. $0.262 B. $1.01 C. $1.55 D. $2.33 E. $3.07

D. $2.33 ($44.55 {au}/55.0L) x (3.785L/1gal) x ($0.7597 {us}/$1 {au}) = 44.55 x 3.785 x 0.7597 / 55.0 = $2.33

Which of the following temperatures is not possible? A. 1001 K B. 1001 °C C. 1 K D. -401 °C E. -401 °F

D. -401 °C Can not be less than absolute zero

Convert 1.500 L to cm3. A. 1.5 × 103 cm3 B. 1.500 cm3 C. 1.5 × 10-3 cm3 D. 1.500 × 103 cm3 E. 1.500 × 10-3 cm3

D. 1.500 × 103 cm3 1 ml = 1 cm3 1 ml = 10-3 L 1.500 L x (1 ml/10-3 L) x (1 cm3/1 ml) = 1.500 x 103 cm3

Convert 42 °C to °F and express the answer to the correct number of significant figures. A. 42 *F B. 107 *F C. 107.6 *F D. 108 *F E. 315 *F

D. 108 *F F=1.8C + 32 = 1.8 (42) + 32 =107.6 = 108 (round to one's place)

Convert 0.000459 to scientific notation. A. 4.59 × 104 B. 0.459 × 103 C. 4.59 × 10-3 D. 4.59 × 10-4 E. 4.59 × 10-5

D. 4.59 × 10-4 Move decimal this way so negative exponent

How many mL are in 45.1 cm3? A. 0.00450 mL B. 4.51 mL C. 0.451 mL D. 45.1 mL E. 45100 mL

D. 45.1 mL 1 ml = 1 cm3

How many significant figures are in 1.0800? A. 3 B. 4 C. 2 D. 5 E. None of the above

D. 5

How many inches are in 16.3 cm? A. 41.4 in B. 6.4 in C. 0.156 in D. 6.42 in E. 32.6 in

D. 6.42 in 16.3cm x (1in/2.54cm) = 6.42in

Which of the following is a physical change? A. Burning butane B. Barbequing a steak C. Decomposing water into hydrogen and oxygen gases D. Breaking a piece of glass E. Baking a cake

D. Breaking a piece of glass

Which of the following is an element? A. Sugar B. Salt C. Brass D. Chlorine E. Air

D. Chlorine Cl is on the periodic table

Boiling point is an example of a... A. physical change. B. chemical change. C. quantitative property. D. physical property. E. chemical property.

D. physical property

Convert 3.23 × 103 to decimal notation. A. 3.23 B. 32.3 C. 323 D. 0.00323 E. 3230

E. 3230

In Australia the highway speed limit is posted at 100. km/hr. What is this in mi/hr? (Note: 1 mi = 5280 ft; 0.6214 mi = 1 km.) A. 100. mi/hr B. 161 mi/hr C. 55.5 mi/hr D. 75.2 mi/hr E. 62.1 mi/hr

E. 62.1 mi/hr (100km/hr) x (0.6214mi/1km) = 62.1 mi/hr

Which of the following is a mixture? A. Seawater B. Iron ore C. Air D. Milk E. All of the above

E. All of the Above All made up of more than one type of matter

Which of the following possess(es) kinetic energy? A. A ball falling through the air B. A dart thrown at a dart board C. A ball rolling down a slide D. An arrow flying through the air E. All of the above

E. All of the above Kinetic energy is energy of MOTION

Which of the following is a chemical change? A. Sugar is dissolved in water. B. Copper metal is rolled into wire. C. Ice melts. D. All of the above E. None of the above

E. None of the above

What is the identity of an unknown object that has a mass of 1.08 kg and displaces 50.5 cm3 of water? (See Table 2.4) A. Copper B. Lead C. Gold D. Aluminum E. Platinum

E. Platinum (1.08kg/50.5cm^3) x (1000g/1kg) = 21.49 g/cm^3

Why do scientists use scientific notation? A. To confuse students B. To write very large numbers simply C. To write very small numbers simply D. All of the above E. Two of the above

E. Two of the above

What are the fundamental SI units of length, mass, time, and temperature respectively? A. km, kg, s, K B. m, g, s, °C C. m, g, s, K D. m, kg, s, °C E. m, kg, s, K

E. m, kg, s, K