21. Which of the following is the correct formula for a compound of nickel and oxygen? (สูตรของสารประกอบระหว่างนิกเกิลกับออกซิเจนข้อใดถูกต้อง)
a) NiO4 b) NiO c) Ni2Od) Ni2O e) NiO2
22. Which of the following is the correct formula for a compound of magnesium and nitrogen? (สู๔ตรของสารประกอบระหว่างแมกนีเซียมกับ ไนโตรเจนข้อใดถูกต้อง)
a) Mg3N b) Mg3N2 c) Mg2N3 d) MgN e) Mg2N
23. Which of the following is the correct formula for a compound of cadmium and chlorine? (สูตรของสารประกอบระหว่างแคดเมียมกับคลอรีนข้อใด ถูกต้อง)
a) CdCl3 b) CdCl2 c) Cd3Cl2 d) CdCl4 e) CdCl
24. The formula of an oxide of gallium is Ga2O3. What is the formula of the perchlorate of gallium with the same oxidation number? (Ans.d) (ถ้า สารประกอบออกไซด์ของแกลเลียมคือ Ga2O3 อยากทราบว่าสารประกอบเปอร์คลอเรตของแกลเลียมจะเป็นดังข้อใด ถ้าเลขออกซิเดชันของแกลเลียมเป็น ค่าเดิม)
a) GaClO4 b) Ga(ClO4)2 c) Ga3(ClO4)2 d) Ga(ClO4)3 e) Ga2(ClO4)3
25. The formula of a carbonate of yttrium is Y2(CO3)3. What is the formula of the nitrate of yttrium with the same oxidation number? (Ans.d) (ถ้าสารประกอบคาร์บอเนตของ yttrium คือ Y2(CO3)3 อยากทราบว่าสารประกอบไนเตรตจะเป็นดังข้อใด ถ้าเลขออกซิเดชันของ yttrium เป็นค่าเดิม)
a) YNO3 b) Y3NO3 c) Y3(NO3)2 d) Y(NO3)3 e) Y2(NO3)3
26. If the formulas of calcium tungstate and cerium tungstate are CaWO4 and Ce2(WO4)3, what is the formula of cerium iodate? (Ans.d)
a) CeIO3 b) Ce2IO3 c) Ce3(IO3)2 d) Ce(IO3)3 e) Ce2(IO3)3
27. Elements of Groups IIIA and VIIA of the periodic table tend to form ions with ___ charges. (Ans.a)
a) +3 and -1 b) +3 and +7 c) +3 and +1 d) +3 and -7 e) -3 and +7
28. An ionic bond is formed between two atoms: (Ans.a) (การเกิดพันธะไอออนิกระหว่างอะตอม 2 อะตอม เป็นดังข้อใด)
a) by transfer of electrons from metallic to nonmetallic elements.
b) whose difference in electronegativities is less than 1.7.
c) by sharing of electrons.
d) by changes in their nuclei.
e) which are both nonmetals.
29. Consider the following elements and arrange them in order of increasing number of electrons depicted in electron dot symbols. Which one occupies the intermediate position in the series? (Ans.a) (ถ้าพิจารณาจากการจัดอิเล็กตรอนแล้ว ธาตุใดจะอยู่ในตำแหน่งของธาตุถึ่งโลหะ)
Si Mg Cl Ga S
a) Si b) S c) Mg d) Ga e) Cl
30. Consider the following elements and arrange them in order of increasing number of electrons depicted in electron dot symbols. Which one occupies the intermediate position in the series? (Ans.a) (ถ้าพิจารณาจากการจัดอิเล็กตรอนแล้ว ธาตุใดจะอยู่ในตำแหน่งของธาตุถึ่งโลหะ)
Al Rb Ba S P
a) Al b) P c) Rb d) S e) Ba
31. Sodium chloride (NaCl) exists as a ccp structure in which the Na+ is located in an octahedral hole. It follows that Na+ has ____ nearest neighbor Cl- ions and Cl- has ____ nearest neighbor Na+ ions. (Ans.a)
a) 6, 6 b) 4, 6 c) 4, 4 d) 2, 2 e) 8, 8
32. CsI exists in a simple cubic arrangement. How many Cs+ and I- ions are contained in the unit cell? (Ans.a)
a) 1, 1 b) 4, 2 c) 2, 4 d) 4, 4 e) 2, 2
33. Consider the following ionic substances and arrange them in order of increasing lattice energy. (Ans.c)
CaS MgS MgO
a) CaS > MgO > MgS b) MgS > CaS > MgO c) MgO > MgS > CaS
d) MgO > CaS > MgS
34. The ionic radii of some ions are: Na+, 0.095 nm; K+, 0.133 nm; Ca2+, 0.099 nm; Ni2+, 0.069 nm; Ba2+, 0.135 nm; Ag+, 0.126 nm; S2-, 0.184 nm; Br-, 0.195 nm; nm; O2-, 0.140 ; Cl-, 0.181 nm. Consider the following compounds and arrange them in order of increasing lattice energy and select the compound which is of intermediate value in the series. (Ans.c)
BaO NaBr AgCl NiS CaS
a) AgCl b) BaO c) NiS d) NaBr e) CaS
35. Consider the following ionic substances and arrange them in order of increasing lattice energy. (Ans.c)
NaI KI LiCl
a) NaI > KI > LiCl b) LiCl > KI > NaI c) LiCl > NaI > KI d) KI > NaI > LiCl
South Pasadena · AP Chemistry Name ____________________________________
Period ___ Date ___/___/___
3 · Molecules & Compounds
Writing Formulas and Naming Compounds
Introduction
Writing formulas and naming compounds can be confusing because there are different types of compounds that follow different rules. Additionally, some compounds (H2O, NH3, CH4, etc.) simply have common names that must be memorized.
The two types of compounds we will focus on first are ionic compounds (formed from positive and negative ions) and binary nonmetal compounds (molecular compounds). Later we will add acids. So… you must recognize the type of compound before you try to name it. [Note: + ion = “cation” and – ion = “anion”.]
Ionic
Binary Nonmetal
Formula
+ ion before – ion
ex: NaCl (NH4)2SO4 Al2S3
usually the less electronegative atom is first
ex: CO CO2 N2O
Naming
Name of cation + name of anion
sodium chloride
ammonium sulfate
aluminum sulfide
Indicate the number (mono, di, tri, and kind of atoms. First element is simply name of element. Second element name ends with “ide”