Question 1

Which of the following statements best explains why noble gases are chemically inert?

Accepted Answer

They have a full outermost electron shell, making them stable according to the octet rule.

Question 2

A sample of chlorine contains two isotopes: $$^{35}\mathrm{Cl} (75.4$$%) and $$^{37}\mathrm{Cl} (24.6$$%). What is the relative atomic mass of chlorine? (Give your answer to one decimal place.)

Accepted Answer

$$35.5$$

Question 3

Which laboratory safety precaution is most important when diluting concentrated sulfuric acid?

Accepted Answer

Add acid slowly to water with stirring.

Question 4

Which of the following ions is colored in aqueous solution?

Accepted Answer

$$\mathrm{Cu}^{2+} ($$blue/green)

Question 5

Which of the following best describes the bonding in a molecule of $$\mathrm{O}_2$$?

Accepted Answer

A double covalent bond formed by sharing two pairs of electrons.

Question 6

A student collects a gas over water. Which property must the gas have for this method to be suitable?

Accepted Answer

The gas must be insoluble in water and not react with water.

Question 7

Which of the following is the correct electronic arrangement for a calcium atom ($$Z=20$$)?

Accepted Answer

$$2,8,8,2$$

Question 8

Which of the following best describes the formation of an ionic bond between sodium and chlorine?

Accepted Answer

Sodium transfers one electron to chlorine, forming $$\mathrm{Na}^+$$ and $$\mathrm{Cl}^-$$ ions.

Question 9

Which of the following is a property of isotopes of the same element?

Accepted Answer

They have the same chemical properties but different physical properties.

Question 10

Which of the following ions is isoelectronic with argon ($$\mathrm{Ar}$$)?

Accepted Answer

$$\mathrm{Cl}^-$$

Question 11

Which of the following best explains why Group I metals become more reactive down the group?

Accepted Answer

The outermost electron is further from the nucleus and more easily lost.

Question 12

What is the formula mass of magnesium chloride ($$\mathrm{MgCl}_2$$)? (Relative atomic masses: Mg = 24, Cl = 35.5)

Accepted Answer

$$95$$

Question 13

Which of the following is a dative covalent bond?

Accepted Answer

The bond between N and H in $$\mathrm{NH}_4^+$$ where both electrons come from N.

Question 14

Which of the following best describes a physical change?

Accepted Answer

Boiling water to form steam.

Question 15

Which of the following is the correct formula for the compound formed between aluminum and oxygen?

Accepted Answer

$$\mathrm{Al}_2\mathrm{O}_3$$

Question 16

Which of the following best describes the trend in reactivity of Group VII elements (halogens) down the group?

Accepted Answer

Reactivity decreases down the group.

Question 17

Which of the following is a correct statement about the Periodic Table?

Accepted Answer

Elements are arranged in order of increasing atomic number.

Question 18

Which of the following is a polyatomic ion?

Accepted Answer

$$\mathrm{SO}_4$$^{2-}$$

Question 19

Which of the following best describes the difference between a cation and an anion?

Accepted Answer

A cation is a positively charged ion, while an anion is a negatively charged ion.

Question 20

Which of the following best explains why solid lead(II) bromide does not conduct electricity, but molten lead(II) bromide does?

Accepted Answer

Ions are mobile in the molten state but fixed in the solid state.

Atoms, Elements, and Bonding: Foundations of Organic Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard