Exercise \(\PageIndex{1}\) Name the compound below. Hint: Is it ionic or covalent? Is the cation predictable or variable? CuCN Hint It is ionic. It is variable, so you must determine the charge needed to make a total of zero charge. Roman numeral is needed. Answer copper (I) cyanide Exercise \(\PageIndex{1}\) Name the compound below. Hint: Is it ionic or covalent? Is the cation predictable or variable? P Cl 5 Hint It is covalent. There is no cation. Use prefixes to tell how many of each element are in the formula. Answer phosphorus pentachloride Exercise \(\PageIndex{1}\) Add exercises text here. Hint It is covalent. There is no cation. Use prefixes to tell how many of each element are in the formula. Answer Add texts here. Do not delete this text first. Exercise \(\PageIndex{1}\) Add exercises text here. Hint It is covalent. There is no cation. Use prefixes to tell how many of each element are in the formula. Answer Add texts here. Do not delete this text first. Exercise \(\PageIndex{1}\) K Ca Rb Sr Out of the four elements listed above, choose the one that has j) the largest radius k) the least ionization energy l) the most metallic character Answer j Rb Answer k Rb Answer l Rb Exercise \(\PageIndex{1}\) The element chlorine is found in nature as a mixture of 35 Cl and 37 Cl. Given that the average atomic mass of chlorine is 35.45 amu, which isotope is more abundant? Answer 35 Cl is more abundant. Since the average mass is closer to 35 amu, you have more of the isotope with a mass of 35 amu than you do of the isotope with a mass of 37 amu. Exercise \(\PageIndex{1}\) If there were chemists on another planet, their periodic table might be different because the elements might have different "natural" abundances. If on the other planet, the element sulfur had the following natural abundances, calculate the average atomic mass that the chemists on that planet would use. 68.44 % is 32 S with mass of 31.9721 amu 23.24 % is 33 S with mass of 32.9715 amu 8.32 % is 34 S with mass of 33.9679 amu Answer Add up (uncertain digits are underlined): 21.8 8 17amu 7.66 2 6 amu 2.8 2 61 amu Total is 32.3 70 4 amu which rounds to 32.37 amu Exercise \(\PageIndex{1}\) Add exercises text here. Answer Add texts here. Do not delete this text first.