$$2\text{Li}(s) + \text{H}_2(g) \rightarrow 2\text{LiH}(s)$$

$$2\text{Na}(s) + \text{Cl}_2(g) \rightarrow 2\text{NaCl}(s)$$

Question 1

Which of the following statements best explains why hydrogen is placed in multiple locations on some periodic tables?

Accepted Answer

Hydrogen shares properties with alkali metals, halogens, and Group 4A elements.

Question 2

Which reaction represents the formation of an ionic hydride?

Accepted Answer

$$2	ext{Li}(s) + 	ext{H}_2(g) ightarrow 2	ext{LiH}(s)$$

Question 3

Which property increases across Period 2 from left to right?

Accepted Answer

Electronegativity

Question 4

Why does beryllium form only covalent compounds, unlike other Group 2A elements?

Accepted Answer

Be$$^{2+}$$ has a very high charge density, making ionic bonding unfavorable.

Question 5

Which of the following best describes the trend in the acidity of oxides across Period 2?

Accepted Answer

Oxides become more acidic from left to right.

Question 6

Which reaction demonstrates the strong reducing ability of alkali metals?

Accepted Answer

$$2	ext{Na}(s) + 	ext{Cl}_2(g) ightarrow 2	ext{NaCl}(s)$$

Question 7

Which of the following explains why alkali metals have low melting points compared to other metals?

Accepted Answer

Their valence electron is far from the nucleus, resulting in weak metallic bonding.

Question 8

Which property is responsible for the high lattice energy of BeCl$$_2$$ compared to NaCl?

Accepted Answer

Be$$^{2+}$$ has a higher charge and smaller radius than Na$$^+.$$

Question 9

Which of the following is a correct statement about the chemistry of boron?

Accepted Answer

Boron is often electron-deficient and acts as a Lewis acid.

Question 10

Which of the following best explains the amphoteric nature of BeO and Al$$_2O$_3$$?

Accepted Answer

They can react with both acids and bases to form salts and water.

Question 11

Which of the following is a real-world application of the catenation property of carbon?

Accepted Answer

The formation of millions of organic compounds, including plastics and pharmaceuticals.

Question 12

Which of the following best describes the trend in metallic character down Group 4A(14)?

Accepted Answer

Metallic character increases down the group.

Question 13

Which of the following statements about the halogens is correct?

Accepted Answer

Fluorine is much more electronegative than the other halogens.

Question 14

Which of the following reactions demonstrates the amphoteric behavior of aluminum oxide?

Accepted Answer

$$	ext{Al}_2	ext{O}_3(s) + 6	ext{HCl}(aq) ightarrow 2	ext{AlCl}_3(aq) + 3	ext{H}_2	ext{O}(l)$$

Question 15

Which of the following best explains why carbon forms so many compounds?

Accepted Answer

Carbon can catenate, forming stable chains, rings, and multiple bonds.

Question 16

Which of the following is a correct statement about the oxides of Group 4A(14) elements?

Accepted Answer

Oxides become more basic as you move down the group.

Question 17

Which of the following best describes the structure of metallic hydrides?

Accepted Answer

Hydrogen atoms and H$$_2$$ molecules occupy holes in the metal crystal lattice.

Question 18

Which of the following is a correct statement about the diagonal relationship in the periodic table?

Accepted Answer

Li and Mg, Be and Al show similar chemical properties due to similar charge density and size.

Question 19

Which of the following best explains why SnCl$$_2$$ and PbCl$$_2$$ are white, crystalline solids while SnCl$$_4 is a $$volatile liquid?

Accepted Answer

SnCl$$_2$$ and PbCl$$_2$$ have greater ionic character due to lower oxidation states.

Periodic Patterns in the Main-Group Elements: Hydrogen, Groups 1A–4A, and Periodic Trends

Guida di studio - Domande di pratica