Determine whether each of the following statements is true or false. a. The nucleus has most of the mass and comprises most of the volume of an atom.

Determine whether each of the following statements is true or false. c. The number of electrons in an atom equals the number of neutrons in the atom.

Determine whether each of the following statements is true or false. d. The protons in the nucleus of the helium atom are held together by a force called the strong nuclear force.

Consider an atom of ¹⁰B. (a) How many protons, neutrons, and electrons does this atom contain?

Consider an atom of ¹⁰B. (b) What is the symbol of the atom obtained by adding one proton to ¹⁰B?

Consider an atom of ¹⁰B. (c) What is the symbol of the atom obtained by adding one neutron to ¹⁰B?

Consider an atom of ¹⁰B. (d) Are either of the atoms obtained in parts (b) and (c) isotopes of ¹⁰B? If so which one?

Consider an atom of ⁶³Cu. (a) How many protons, neutrons, and electrons does this atom contain?

Consider an atom of ⁶³Cu. b. What is the symbol of the ion obtained by removing two electrons from ⁶³Cu?

Consider an atom of ⁶³Cu. (c) What is the symbol for the isotope of ⁶³Cu that possesses 36 neutrons?

(a) Define atomic number and mass number.

(b) Which of these can vary without changing the identity of the element?

(a) Which two of the following are isotopes of the same element: ³¹₁₆X, ³¹₁₅X, ³²₁₆X?

(b) What is the identity of the element whose isotopes you have selected?

How many protons, neutrons, and electrons are in the following atoms? (a) ⁸⁴Kr (b) ²⁰⁰Hg (c) ⁷⁰Ga

How many protons, neutrons, and electrons are in the following atoms? (d) ⁸⁰Br

How many protons, neutrons, and electrons are in the following atoms? (e) ¹⁸⁴W (f) ¹⁸¹Ta.

Fill in the gaps in the following table, assuming each column represents a neutral atom.

Symbol ⁷⁹Br

Protons 25 82

Neutrons 30 64

Electrons 48 86

Mass no. 222 207

Complete the third row of the table.

Fill in the gaps in the following table, assuming each column represents a neutral atom.

Symbol ⁷⁹Br

Protons 25 82

Neutrons 30 64

Electrons 48 86

Mass no. 222 207

Complete the fourth row of the table.

Fill in the gaps in the following table, assuming each column represents a neutral atom.

Symbol ⁷⁹Br

Protons 25 82

Neutrons 30 64

Electrons 48 86

Mass no. 222 207

Complete the fifth row of the table.

Fill in the gaps in the following table, assuming each column represents a neutral atom.

Symbol ¹¹²Cd

Protons 38 92

Neutrons 58 49

Electrons 38 36

Mass no. 81 235

Complete the first row of the table.

Fill in the gaps in the following table, assuming each column represents a neutral atom.

Symbol ¹¹²Cd

Protons 38 92

Neutrons 58 49

Electrons 38 36

Mass no. 81 235

Complete the second row of the table.

Write the correct symbol, with both superscript and subscript, for each of the following. Use the list of elements in the front inside cover as needed: (a) the isotope of platinum that contains 118 neutrons

Write the correct symbol, with both superscript and subscript, for each of the following. Use the list of elements in the front inside cover as needed: (b) the isotope of krypton with mass number 84 (c) the isotope of rhenium with mass number 187

Write the correct symbol, with both superscript and subscript, for each of the following. Use the list of elements in the front inside cover as needed: (d) the isotope of magnesium that has an equal number of protons and neutrons.

The atomic weight of boron is reported as 10.81, yet no atom of boron has the mass of 10.81 amu. Which is the best explanation?

a. The measurement of atomic mass is only reliable to two significant figures.

b. The atomic weight is an average of many individual atoms.

c. The atomic weight is an average of many isotopes of the same nuclear composition.

Only two isotopes of copper occur naturally: ⁶³Cu (atomic mass = 62.9296 amu; abundance 69.17%) ⁶⁵Cu (atomic mass = 64.9278 amu; abundance 30.83%). Calculate the atomic weight (average atomic mass) of copper.

Rubidium has two naturally occurring isotopes, rubidium-85 (atomic mass = 84.9118 amu; abundance = 72.15%) and rubidium-87 (atomic mass = 86.9092 amu; abundance = 27.85%). Calculate the atomic weight of rubidium

(a) Thomson's cathode-ray tube (Figure 2.4) and the mass spectrometer (Figure 2.11) both involve the use of electric or magnetic fields to deflect charged particles. What are the charged particles involved in each of these experiments?