Why Do Family of Elements Have Similar Properties

Chemistry Homework: Periodic properties & Chemical Bonding

1. Fill in the blanks a) Electron orbitals have different shapes: s-orbitals are ______b) The periodic law states that when elements are arranged in order of increasing ______, elements with similar properties occur in the same ______. c) In the modern periodic table, the vertical columns are called ______d) Metals are on the ______side of the periodic table e) It requires energy to ______an electron from a neutral atom. It results in the formation of ______charged species known as ______. f) Nobel gasses have completed ______shell with a total of ______electrons. g) The family of element from with it is easiest to remove an electron is called ______and they have ______electron (s) in their ______shell. h) Atomic size within a period ______as one move from left to right. i) Electron affinity is the______required to ______an ______to an element. j) The electron attracting tendency of elements is known as ______. ______has the most and ______has the least tendency.

2. Why do family of elements have similar properties?

3. With reference only to the periodic table, arrange the following atoms in terms of: a) Increasing ionization energies: O, Rb, Br, Ca, Sc, Se, F, Cs, He. b) Decreasing metallic character: I, O, Cs, K, Te, F, Mg, Al. c) The largest atom: H, Ar, Ag, Ba, Te, Au d) The most negative electron affinity: Na, I, Ba, Se, Cl, P e) Number of 2p electrons in N f) Number of 4s electrons in Rb g) Number of elements in Group 14 h) Increasing order of electronegativities: Br, Cr. Ag, Ba, C. O, Fr 4. a) Provide the element with largest radius: S2-, Cl, Cl- , K+, S b) Provide the element with the largest atomic radius from the following: Be S Na P O c) Provide the element with the largest electronegativity value from the following: Cs Rh Se Ca Mn d) Provide the most metallic element from the following: Ti Br Sn Sr Ag g) Provide the element with the greatest first ionization energy from the following K Li C F O

5. For which of the following pairs of elements would bonding be primarily ionic? a. C and Cl b. Cu and I c. Mg and Cl d. C and S

6. Isoelectric (same electronic configuration) species have the same electron configuration. Which of the following does not belong in the same group of isoelectric species with the others? a. N3- b. F- c. Na+ d. Ar

7. Which of the following contributes most directly to the existence of a higher boiling point for H2O than H2S?

8. Which of the following molecules is not linear? (Hint!!! Try to write the Lewis Bond structure first and apply VBEPR) a. BeCl2 b. C2H2 c. SO2 d. BeH2 9. Draw the Lewis Bond structure of the following molecules: a) CCl4 (C is the central atom) b) ONCl (N is the central atom) c) HONO (Atoms arrange H O N O) d) COCl2 ( C is the central atom) e) HCN (C is the central atom)

10. N2 (gas) has exceptionally high bond energy. Predict the number of bonds 2+ in N2 . 11. Which molecule has the most ionic character a. MgS b. HCl c. CO2 d. CaO 12. Which molecule has the greatest polarity? e. Fluorine f. Hydrogen fluoride g. Hydrogen chloride h. Tetrafluoromethane (CF4)

13. When hydrogen bonds with sulfur it makes a gas, when it bonds with oxygen, it makes a liquid. If sulfur and oxygen are in the same family, why are the properties of H2S and H2O so different?

14.State and explain the trend in melting point for the group 1 elements.

15. Predict the shapes and write the proper structural name of the following compounds according to the VSEPR (Valence Shell electron Repulsion) theory.

-2 a) CO3

b) SiF4

c) PH3

d) SO2