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문제 28
Identify the elements that have molecules as their basic units. a. hydrogen b. iodine c. lead d. oxygen
문제 29
A hydrogen-filled balloon is ignited and 1.50 g of hydrogen is reacted with 12.0 g of oxygen. How many grams of water vapor form? (Assume that water vapor is the only product.)
문제 30
An automobile gasoline tank holds 21 kg of gasoline. When the gasoline burns, 84 kg of oxygen is consumed, and carbon dioxide and water are produced. What is the total combined mass of carbon dioxide and water that is produced?
문제 31
Two samples of carbon tetrachloride are decomposed into their constituent elements. One sample produces 38.9 g of carbon and 448 g of chlorine, and the other sample produces 14.8 g of carbon and 134 g of chlorine. Are these results consistent with the law of definite proportions? Explain your answer.
- Two samples of sodium chloride are decomposed into their constituent elements. One sample produces 6.98 g of sodium and 10.7 g of chlorine, and the other sample produces 11.2 g of sodium and 17.3 g of chlorine. Are these results consistent with the law of definite proportions? Explain your answer.
문제 32
문제 33
The mass ratio of sodium to fluorine in sodium fluoride is 1.21:1. A sample of sodium fluoride produces 28.8 g of sodium upon decomposition. How much fluorine (in grams) forms?
문제 34
Upon decomposition, one sample of magnesium fluoride produces 1.65 kg of magnesium and 2.57 kg of fluorine. A second sample produces 1.32 kg of magnesium. How much fluorine (in grams) does the second sample produce?
문제 35
Two different compounds containing osmium and oxygen have the following masses of oxygen per gram of osmium: 0.168 and 0.3369 g. Show that these amounts are consistent with the law of multiple proportions.
문제 36
Palladium forms three different compounds with sulfur. The mass of sulfur per gram of palladium in each compound is listed here. Show that these masses are consistent with the law of multiple proportions. Compound Grams S per Gram Pd A 0.603 B 0.301 C 0.151
문제 37
Sulfur and oxygen form both sulfur dioxide and sulfur trioxide. When samples of these are decomposed, the sulfur dioxide produces 3.49 g oxygen and 3.50 g sulfur, while the sulfur trioxide produces 6.75 g oxygen and 4.50 g sulfur. Calculate the mass of oxygen per gram of sulfur for each sample and show that these results are consistent with the law of multiple proportions.
문제 38
Sulfur and fluorine form several different compounds including sulfur hexafluoride and sulfur tetrafluoride. Decomposition of a sample of sulfur hexafluoride produces 4.45 g of fluorine and 1.25 g of sulfur, while decomposition of a sample of sulfur tetrafluoride produces 4.43 g of fluorine and 1.87 g of sulfur. Calculate the mass of fluorine per gram of sulfur for each sample and show that these results are consistent with the law of multiple proportions.
문제 39
Which statements are consistent with Dalton's atomic theory as it was originally stated? Why? a. Sulfur and oxygen atoms have the same mass. b. All cobalt atoms are identical. c. Potassium and chlorine atoms combine in a 1:1 ratio to form potassium chloride. d. Lead atoms can be converted into gold.
문제 40
Which statements are inconsistent with Dalton's atomic theory as it was originally stated? Why? a. All carbon atoms are identical. b. An oxygen atom combines with 1.5 hydrogen atoms to form a water molecule. c. Two oxygen atoms combine with a carbon atom to form a carbon dioxide molecule. d. The formation of a compound often involves the destruction of one or more atoms.
문제 41
Which statements are consistent with Rutherford's nuclear theory as it was originally stated? Why? a. The volume of an atom is mostly empty space. b. The nucleus of an atom is small compared to the size of the atom. c. Neutral lithium atoms contain more neutrons than protons. d. Neutral lithium atoms contain more protons than electrons.
문제 42
Which statements are inconsistent with Rutherford's nuclear theory as it was originally stated? Why? a. Since electrons are smaller than protons, and since a hydrogen atom contains only one proton and one electron, it must follow that the volume of a hydrogen atom is mostly due to the proton. b. A nitrogen atom has 7 protons in its nucleus and 7 electrons outside of its nucleus. c. A phosphorus atom has 15 protons in its nucleus and 150 electrons outside of its nucleus. d. The majority of the mass of a fluorine atom is due to its 9 electrons.
문제 43
A chemist in an imaginary universe, where electrons have a different charge than they do in our universe, performs the Millikan oil drop experiment to measure the electron's charge. The charges of several drops are recorded here. What is the charge of the electron in this imaginary universe?
Drop # Charge
A –6.9×10–19 C
B –9.2×10–19 C
C –11.5×10–19 C
D –4.6×10–19 C
문제 44
Imagine a unit of charge called the zorg. A chemist performs the oil drop experiment and measures the charge of each drop in zorgs. Based on the results shown here, what is the charge of the electron in zorgs (z)? How many electrons are in each drop?
Drop # Charge
A –4.8×10–9 z
B –9.6×10–9 z
C –6.4×10–9 z
D –12.8×10–9 z
문제 45a
On a dry day, your body can accumulate static charge from walking across a carpet or from brushing your hair. If your body develops a charge of -15 µC (microcoulombs), how many excess electrons has it acquired?
문제 45b
On a dry day, your body can accumulate static charge from walking across a carpet or from brushing your hair. If your body develops a charge of -15 µC (microcoulombs), what is their collective mass?
문제 46
How many electrons are necessary to produce a charge of -1.0 C? What is the mass of this many electrons?
문제 47
Which statements about subatomic particles are true? a. If an atom has an equal number of protons and electrons, it will be charge-neutral. b. Electrons are attracted to protons. c. Electrons are much lighter than neutrons. d. Protons have twice the mass of neutrons.
문제 48
Which statements about subatomic particles are false? a. Protons and electrons have charges of the same magnitude but opposite sign. b. Protons have about the same mass as neutrons. c. Some atoms don't have any protons. d. Protons and neutrons have charges of the same magnitude but opposite signs.
문제 49
How many electrons does it take to equal the mass of a proton?
문제 50
A helium nucleus has two protons and two neutrons. How many electrons does it take to equal the mass of a helium nucleus?
문제 51a
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. a. the silver isotope with 60 neutrons
문제 51b
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. b. the silver isotope with 62 neutrons
문제 51c
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. c. the uranium isotope with 146 neutrons
문제 51d
Write isotopic symbols in the form X-A (e.g., C-13) for each isotope. d. the hydrogen isotope with one neutron
문제 52a
Write isotopic symbols in the form AZX for each isotope. a. the copper isotope with 34 neutrons
문제 52b
Write isotopic symbols in the form AZX for each isotope. b. the copper isotope with 36 neutrons
