Chapter 2 Questions - Ch 2 Multiple Choice Identify the...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Ch 2 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. ____ 1. 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, chlorine, nitrogen b. carbon, sulfur, phosphorus, hydrogen c. oxygen, hydrogen, calcium, sodium d. carbon, hydrogen, nitrogen, oxygen e. carbon, oxygen, sulfur, calcium ____ 2. 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? a. nitrogen b. calcium c. iodine d. sodium e. phosphorus ____ 3. Which of the following statements is false ? a. Atoms of the various elements differ in their number of subatomic particles. b. All atoms of a particular element have the same number of protons in their nuclei. c. The neutrons and protons present in the nucleus of an atom are almost identical in mass; each has a mass of about 1 dalton. d. An atom is the smallest unit of an element that still retains the properties of the element. e. Protons and electrons are electrically charged particles. Protons have one unit of negative charge, and electrons have one unit of positive charge. ____ 4. Each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atom's nucleus? a. atomic mass b. atomic weight c. atomic number d. mass weight e. mass number ____ 5. The mass number of an element can be easily approximated by adding together the number of ____ in an atom of that element. a. protons and neutrons b. energy levels c. protons and electrons d. neutrons and electrons e. isotopes ____ 6. What is the approximate atomic mass of an atom with 16 neutrons, 15 protons, and 15 electrons? a. 15 daltons b. 16 daltons c. 30 daltons d. 31 daltons e. 46 daltons ____ 7. Oxygen has an atomic number of 8 and a mass number of 16. Thus, the atomic mass of an oxygen atom is a. exactly 8 grams.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
b. exactly 8 daltons. c. approximately 16 grams. d. approximately 16 daltons. e. 24 amu (atomic mass units). ____ 8. 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 grams and an atomic number of 14. e. The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons. ____ 9.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/13/2010 for the course ACT 101 taught by Professor Jenkins during the Spring '10 term at Alabama State University.

Page1 / 11

Chapter 2 Questions - Ch 2 Multiple Choice Identify the...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online