Problem 2.1QP Problem 2.2QP: Name the types of radiation known to be emitted by radioactive elements. Problem 2.3QP: Compare the properties of the following: particles, cathode rays, protons, neutrons, electrons. Problem 2.4QP: What is meant by the term fundamental particle? Problem 2.5QP: Describe the contributions of the following scientists to our knowledge of atomic structure: J. J.... Problem 2.6QP: Describe the experimental basis for believing that the nucleus occupies a very small fraction of the... Problem 2.7QP: The diameter of a helium atom is about 1 102 pm. Suppose that we could line up helium atoms side by... Problem 2.8QP Problem 2.9QP: Use the helium-4 isotope to define atomic number and mass number. Why does a knowledge of atomic... Problem 2.10QP: Why do all atoms of an element have the same atomic number, although they may have different mass... Problem 2.11QP: What do we call atoms of the same elements with different mass numbers? Problem 2.12QP: Explain the meaning of each term in the symbol XZA. Problem 2.13QP: What is the mass number of an iron atom that has 28 neutrons? Problem 2.14QP: Calculate the number of neutrons in 239Pu. Problem 2.15QP Problem 2.16QP: Indicate the number of protons, neutrons, and electrons in each of the following species:... Problem 2.17QP: Write the appropriate symbol for each of the following isotopes: (a) Z = 11, A = 23; (b) Z = 28, A =... Problem 2.18QP: Write the appropriate symbol for each of the following isotopes: (a) Z = 74, A = 186; (b) Z = 80, A... Problem 2.19QP: What is the periodic table, and what is its significance in the study of chemistry? Problem 2.20QP: State two differences between a metal and a nonmetal. Problem 2.21QP: Write the names and symbols for four elements in each of the following categories: (a) nonmetal, (b)... Problem 2.22QP: Define, with two examples, the following terms: (a) alkali metals, (b) alkaline earth metals, (c)... Problem 2.23QP Problem 2.24QP: Describe the changes in properties (from metals to nonmetals or from nonmetals to metals) as we move... Problem 2.25QP: Consult a handbook of chemical and physical data (ask your instructor where you can locate a copy of... Problem 2.26QP: Group the following elements in pairs that you would expect to show similar chemical properties: K,... Problem 2.27QP Problem 2.28QP Problem 2.29QP: Describe the two commonly used molecular models. Problem 2.30QP Problem 2.31QP Problem 2.32QP Problem 2.33QP: Identify the following as elements or compounds: NH3, N2, S8, NO, CO, CO2, H2, SO2. Problem 2.34QP Problem 2.35QP: Give the number of protons and electrons in each of the following common ions: Na+, Ca2+, Al3+,... Problem 2.36QP: Give the number of protons and electrons in each of the following common ions: K+, Mg2+, Fe3+, Br,... Problem 2.37QP: Pair the following species that contain the same number of electrons: Ar, Sn4+, F, Fe3+, P3, V, Ag+,... Problem 2.38QP: Write the correct symbols for the atoms that contain: (a) 25 protons, 25 electrons, and 27 neutrons;... Problem 2.39QP: What does a chemical formula represent? What is the ratio of the atoms in the following molecular... Problem 2.40QP: Define molecular formula and empirical formula. What are the similarities and differences between... Problem 2.41QP: Give an example of a case in which two molecules have different molecular formulas but the same... Problem 2.42QP Problem 2.43QP Problem 2.44QP Problem 2.45QP Problem 2.46QP Problem 2.47QP: What are the empirical formulas of the following compounds? (a) C2N2, (b) C6H6, (c) C9H20, (d)... Problem 2.48QP: What are the empirical formulas of the following compounds? (a) Al2Br6, (b) Na2S2O4, (c) N2O5, (d)... Problem 2.49QP: Write the molecular formula of glycine, an amino acid present in proteins. The color codes are:... Problem 2.50QP: Write the molecular formula of ethanol. The color codes are: black (carbon), red (oxygen), and gray... Problem 2.51QP Problem 2.52QP Problem 2.53QP Problem 2.54QP Problem 2.55QP Problem 2.56QP Problem 2.57QP Problem 2.58QP Problem 2.59QP: Name these compounds: (a) Na2CrO4, (b) K2HPO4, (c) HBr (gas), (d) HBr (in water), (e) Li2CO3, (f)... Problem 2.60QP Problem 2.61QP Problem 2.62QP Problem 2.63QP: Sulfur (S) and fluorine (F) form several different compounds. One of them, SF6, contains 3.55 g of F... Problem 2.64QP Problem 2.65QP Problem 2.66QP: In which one of the following pairs do the two species resemble each other most closely in chemical... Problem 2.67QP Problem 2.68QP Problem 2.69QP: Determine the molecular and empirical formulas of the compounds shown here. (Black spheres are... Problem 2.70QP: What is wrong with or ambiguous about the phrase four molecules of NaCl? Problem 2.71QP Problem 2.72QP: Which of the following are elements, which are molecules but not compounds, which are compounds but... Problem 2.73QP Problem 2.74QP Problem 2.75QP: Each of the following pairs of elements will react to form an ionic compound. Write the formulas and... Problem 2.76QP: Match the descriptions [(a)(h)] with each of the following elements: P, Cu, Kr, Sb, Cs, Al, Sr, Cl.... Problem 2.77QP: Explain why anions are always larger than the atoms from which they are derived, whereas cations are... Problem 2.78QP Problem 2.79QP: Caffeine, shown here, is a psychoactive stimulant drug. Write the molecular formula and empirical... Problem 2.80QP Problem 2.81QP Problem 2.82QP Problem 2.83QP: Fill in the blanks in the following table. Problem 2.84QP Problem 2.85QP: Write the formula of the common ion derived from each of the following: (a) Li, (b) S, (c) I, (d) N,... Problem 2.86QP Problem 2.87QP Problem 2.88QP: Of the 118 elements known, only two are liquids at room temperature (25C). What are they? (Hint: One... Problem 2.89QP Problem 2.90QP Problem 2.91QP Problem 2.92QP Problem 2.93QP Problem 2.94QP Problem 2.95QP: List five elements each that are (a) named after places, (b) named after people, (c) named after a... Problem 2.96QP Problem 2.97QP: Fluorine reacts with hydrogen (H) and deuterium (D) to form hydrogen fluoride (HF) and deuterium... Problem 2.98QP Problem 2.99QP: Identify each of the following elements: (a) a halogen whose anion contains 36 electrons, (b) a... Problem 2.100QP Problem 2.101QP: Show the locations of (a) alkali metals, (b) alkaline earth metals, (c) the halogens, and (d) the... Problem 2.102QP: Fill the blanks in the following table. Problem 2.103QP Problem 2.104QP: In Section 2.1 it was pointed out that mass and energy are alternate aspects of a single entity... Problem 2.105QP: Draw all possible structural formulas of the following hydrocarbons: CH4, C2H6, C3H8, C4H10, C5H12. Problem 2.106QP Problem 2.107QP: Draw two different structural formulas based on the molecular formula C2H6O. Is the fact that you... Problem 2.108QP Problem 2.109QP Problem 2.110QP: A monatomic ion has a charge of +2. The nucleus of the parent atom has a mass number of 55. If the... Problem 2.111QP: In the following 2 2 crossword, each letter must be correct four ways: horizontally, vertically,... Problem 2.112QP Problem 2.113QP Problem 2.114QP Problem 2.115QP Problem 2.116QP Problem 2.117QP Problem 2.118QP Problem 2.119QP Problem 2.120QP Problem 2.121QP Problem 2.122QP: One technique proposed for recycling plastic grocery bags is to heat them at 700C and high pressure... format_list_bulleted