Chapter 2: The Chemical Context of Life (Multiple-Choice Questions)
Why is each element unique and different from other elements in chemical properties? A) Each element has a unique atomic mass. B) Each element has a unique atomic weight. C) Each element has a unique number of protons in its nucleus. D) Each element has a unique number of neutrons in its nucleus. E) Each element has different radioactive properties.
C) Each element has a unique number of protons in its nucleus.
Which of the following statements is false? A) Carbon, hydrogen, oxygen, and nitrogen are the most abundant elements of living matter. B) Some trace elements are very abundant on Earth. C) Virtually all organisms require the same elements in the same quantities. D) Iron is an example of an element needed by all organisms. E) Other than some trace elements, animals are mostly made up of the same elements as plants, in similar proportions.
C) Virtually all organisms require the same elements in the same quantities.
Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates, but not by other organisms such as bacteria or plants? A) nitrogen B) calcium C) iodine D) sodium E) phosphorus
C) iodine
In what way are elements in the same column of the periodic table the same? A) They have the same number of protons. B) They have the same number of neutrons. C) They have the same number of electrons. D) They have the same number of electrons in their valence shell. E) They have the same number of electron shells.
D) They have the same number of electrons in their valence shell.
Oxygen has an atomic number of 8 and a mass number of 16. Thus, what is the atomic mass of an oxygen atom? A) exactly 8 grams B) exactly 8 daltons C) approximately 16 grams D) approximately 16 daltons E) 24 amu (atomic mass units)
D) approximately 16 daltons
About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter? A) carbon, sodium, hydrogen, nitrogen B) carbon, oxygen, phosphorus, hydrogen C) oxygen, hydrogen, calcium, nitrogen D) carbon, hydrogen, nitrogen, oxygen E) carbon, oxygen, nitrogen, calcium
D) carbon, hydrogen, nitrogen, oxygen
Knowing just the atomic mass of an element allows inferences about which of the following? A) the chemical properties of the element B) the number of protons in the element C) the number of neutrons in the element D) the number of protons plus neutrons in the element E) both the number of protons and the chemical properties of the element
D) the number of protons plus neutrons in the element
The nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen? A) The nitrogen atom has a mass number of approximately 7 daltons and an atomic mass of 14. B) The nitrogen atom has a mass number of approximately 14 daltons and an atomic mass of 7. C) The nitrogen atom has a mass number of 14 and an atomic mass of 7 grams. D) The nitrogen atom has a mass number of 7 and an atomic number of 14. E) The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons.
E) The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons.
What factors are most important in determining which elements are most common in living matter? A) the relative abundances of the elements in Earth's crust and atmosphere B) the emergent properties of the simple compounds made from these elements C) the reactivity of the elements with water D) the chemical stability of the elements E) both the relative abundances of the elements and the emergent properties of the compounds made from these elements
E) both the relative abundances of the elements and the emergent properties of the compounds made from these elements