Questions and Answers of Chemistry A Molecular Approach

Which property of rubbing alcohol is a chemical property?a) Density (0.786 g/cm3) b) Flammabilityc) Boiling point (82.5 °C) d) Melting point (-89 °C)
What type of energy is chemical energy?(a) Kinetic energy(b) Thermal energy(c) Potential energy
Describe the scientific approach to knowledge. How does it differ from other approaches?
The diagram on the left represents liquid water molecules in a pan. Which of the three diagrams (a, b, or c) best represents the water molecules after they have been vaporized by boiling? (a) (b) (c)
Which change is a physical change?a) Wood burning b) Iron rustingc) Dynamite exploding d) Gasoline evaporating
A man receives a platinum ring from his fiancée. Before the wedding, he notices that the ring feels a little light for its size, and so he decides to determine its density.He places the ring on a
Explain the main goal of chemistry.
This image represents a particulate view of a sample of matter. Classify the sample according to its composition.a) The sample is a pure element.b) The sample is a homogeneous mixture.c) The sample
In these images, a blue circle represents an atom of one type of element, and a red square represents an atom of a second type of element. Which image is a pure substance? (a) (b) (c) None of the
A sick child has a temperature of 40.00 °C. What is the child’s temperature in (a) K and (b) °F?
Explain this statement in your own words and give an example.The properties of the substances around us depend on the atoms and molecules that compose them.
A chemist mixes sodium with water and witnesses a violent reaction between the metal and water. This is best classified as a) An observation. b) A law.c) A hypothesis. d) A theory.
Which statement best explains the difference ANSWER NOW! between a law and a theory?(a) A law is truth; a theory is mere speculation.(b) A law summarizes a series of related observations; a theory
The graph that follows shows the area of a circle as a function of its radius. What is the radius of a circle that has an area of 155 square inches?a) 7.0 inches b) 6.5 inchesc) 6.8 inches d) 6.2
Determine whether each change is physical or chemical. What kind of property (chemical or physical) is demonstrated in each case?(a) The evaporation of rubbing alcohol. (b) The burning of lamp
What is the difference between a physical property and a chemical property?
Explain how distillation is used to separate mixtures.
A wooden block has a volume of 18.5 in3. Express the volume of the cube in cm3.a) 303 cm3 b) 47.0 cm3c) 1.13 cm3 d) 7.28 cm3
What kind of mixtures can be separated by filtration?
The gas mileage of a certain German automobile is 22 km/L.Convert this quantity to miles per gallon.a) 9.4 mi/gal b) 1.3 * 102 mi/galc) 52 mi/gal d) 3.6 mi/gal
Explain the difference between a homogeneous and a heterogeneous mixture.
A solid metal sphere has a radius of 3.53 cm and a mass of 1.796 kg. What is the density of the metal in g/cm3?a) 34.4 g/cm3 b) 0.103 g/cm3c) 121 g/cm3 d) 9.75 g/cm3
Examine the graph in Figure 1.14 and answer each question.(a) What was the concentration of carbon dioxide in 1960?(b) What was the concentration in 2010?(c) How much did the concentration increase
Three samples, each of a different substance, are weighed, and their volume is measured. The results are tabulated. List the substances in order of decreasing density.a) III > II > Ib) I >
Explain the difference between an element and a compound.
Find the density (in g/cm3) of a metal cylinder with a mass (m) of 8.3 g, a length (l ) of 1.94 cm, and a radius (r) of 0.55 cm. For a cylinder, V = πr2l. GIVEN: m = 8.3 g 1, r FIND: d in
The first diagram depicts a compound in its liquid state.Which of the other diagrams best depicts the compound after it has evaporated into a gas? (a) (b)
Find the radius (r) in centimeters of a spherical water droplet with a volume (V ) of 0.058 cm3. For a sphere, V = (4>3) πr3. GIVEN: V = 0.058 cm³ FIND: r in cm CONCEPTUAL
Explain the difference between a pure substance and a mixture
The mass of fuel in a jet must be calculated before each flight to ensure that the jet is not too heavy to fly. A 747 is fueled with 173,231 L of jet fuel. If the density of the fuel is 0.768 g/cm3,
What is the difference between a crystalline solid and an amorphous solid?
Convert 1285 cm2 to m2.a) 1.285 * 107 m2 b) 12.85 m2c) 0.1285 m2 d) 1.285 * 105 m2
How do solids, liquids, and gases differ?
Perform the calculation to the correct number of significant figures.(8.01 - 7.50)/3.002a) 0.1698867 b) 0.17c) 0.170 d) 0.1699
Calculate the displacement (the total volume of the cylinders through which the pistons move) of a 5.70-L automobile engine in cubic inches. SORT Sort the information in the problem into given
What are two different ways to classify matter?
Convert 1.8 quarts to cubic centimeters. GIVEN: 1.8 qt FIND: cm³ CONCEPTUAL PLAN qt 1L 1.057 qt L 1 mL 10-³ L RELATIONSHIPS USED 1.057 qt = 1 L mL 1 mL cm³ 1 mL = 10-³L 1 mL = 1 cm³ (These
Perform the calculation to the correct number of significant figures. (43.998 * 0.00552)/2.002a) 0.121 b) 0.12c) 0.12131 d) 0.1213
What is wrong with the expression “That is just a theory,” if by theory the speaker is referring to a scientific theory?
What is the mass of a 1.75 L sample of a liquid that has a density of 0.921 g/mL?a) 1.61 * 103 g b) 1.61 * 10-3 gc) 1.90 * 103 g d) 1.90 * 10-3 g
Convert 1.76 yards to centimeters. GIVEN: 1.76 yd FIND: cm CONCEPTUAL PLAN yd 1 m 1.094 yd m 1 cm 102 m RELATIONSHIPS USED 1.094 yd = 1 m 1 cm = 10-²m cm (These conversion factors are from Tables
The density of copper decreases as temperature increases (as does the density of most substances). Which change occurs in a sample of copper when it is warmed from room temperature to 95 °C?(a) The
What theory did John Dalton formulate?
Express the quantity 33.2 * 10-4 m in mm.a) 33.2 mm b) 3.32 mmc) 0.332 mm d) 3.32 * 10-6 mm
Which prefix multiplier is most appropriate for reporting a measurement of 5.57 * 10-5 m?(a) Mega(b) Milli(c) Micro(d) Kilo
Perform each calculation to the correct number of significant figures.(a) 1.10 * 0.5120 * 4.0015 / 3.4555(b)(c) 4.562 * 3.99870 / (452.6755 - 452.33)(d) (14.84 * 0.55) - 8.02 0.355 +105.1 -100.5820

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