23. Chemistry of the Nonmetals

Write and balance a reaction for formation of an ionic hydride with sodium.

Provide a balanced equation for the reaction of hydrogen gas with bromine gas.

Classify each hydride according to its type.

i) SbH₃          _____________________

ii) NaH          _____________________

iii) PdH_0.5      _____________________

iv) CaH₂        _____________________

The following pictures represent structures of the hydrides of four second-row elements:

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(2) <IMAGE>

(3) <IMAGE>

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(a) Which compound has the highest melting point?

Look at the location of elements A, B, C, and D in the following periodic table:

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Which hydride has the lowest boiling point?

In the following pictures of binary hydrides, ivory spheres

represent H atoms or ions, and burgundy spheres represent

atoms or ions of the other element.

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(2) <IMAGE>

(3) <IMAGE>

(4) <IMAGE>

(b) What is the oxidation state of hydrogen in compounds (1), (2), and (3)? What is the oxidation state of the other

element?

The following models represent the structures of binary hydrides of second-row elements:

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b. Draw an electron-dot structure for each hydride. For which hydride is there a problem in drawing the structure? Explain.

Consider the elements C, Se, B, Sn, and Cl. Identify which of these elements:

e. Forms a hydride with the empirical formula 

Look at the location of elements A, B, C, and D in the following

periodic table:

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(a) Write the formula of the simplest binary hydride of each element.

The following models represent the structures of binary hydrides

of second-row elements:

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(a) Identify the nonhydrogen atom in each case, and write the molecular formula for each hydride.

The following pictures represent structures of the hydrides of four second-row elements:

(1) <IMAGE>

(2) <IMAGE>

(3) <IMAGE>

(4) <IMAGE>

(b) Which compound has the lowest boiling point?

In the following pictures of binary hydrides, ivory spheres

represent H atoms or ions, and burgundy spheres represent

atoms or ions of the other element.

(1) <IMAGE>

(2) <IMAGE>

(3) <IMAGE>

(4) <IMAGE>

(a) Identify each binary hydride as ionic, covalent, or interstitial.

(b) What is the oxidation state of hydrogen in compounds (1), (2), and (3)? What is the oxidation state of the other

element?

Which of the following elements (X) will form a covalent hydride with the formula XH₃ that is a gas at room temperature? (LO 22.4)

(a) Al (b) As (c) Ba (d) Se

Compare some of the physical properties of H₂S, NaH, and PdH_x.

What is a nonstoichiometric compound? Give an example, and account for its lack of stoichiometry in terms of structure.

Explain why the hydrogen atoms in interstitial hydrides are mobile.