1.
Ionic bonds always form between metals and ___________.
Correct Answer
A. Nonmetals
Explanation
Ionic bonds occur when there is a transfer of electrons from a metal atom to a nonmetal atom. Nonmetals have a higher electronegativity, meaning they have a stronger attraction for electrons compared to metals. This makes nonmetals more likely to gain electrons and form negative ions. Metals, on the other hand, have a lower electronegativity and are more likely to lose electrons and form positive ions. Therefore, ionic bonds always form between metals and nonmetals.
2.
Negatively charged ions, called ____________, result from gain of electrons.
Correct Answer
B. Anions
Explanation
Negatively charged ions, called anions, result from the gain of electrons. Anions are formed when an atom or molecule gains one or more electrons, resulting in an excess of negative charge. This gain of electrons increases the overall negative charge of the ion, making it negatively charged. Cations, on the other hand, are positively charged ions that result from the loss of electrons. Therefore, in this context, the correct answer is anions.
3.
Positively charged ions, called ____________, result from loss of electrons.
Correct Answer
A. Cations
Explanation
Positively charged ions, called cations, are formed when an atom loses one or more electrons. This loss of electrons creates an imbalance between the positive protons in the nucleus and the negative electrons, resulting in a net positive charge. Therefore, cations are the correct answer since they are positively charged ions that are formed by the loss of electrons.
4.
When an electron is added to or removed from an atom, the atom becomes a(n) ________.
Correct Answer
A. Ion
Explanation
When an electron is added to or removed from an atom, the atom becomes an ion. An ion is an atom that has gained or lost one or more electrons, resulting in a net positive or negative charge. This process is known as ionization.
5.
How does a magnesium atom form a bond with an oxygen atom?
Correct Answer
A. By giving one pair of electrons to the oxygen atom.
Explanation
Magnesium will transfer two electrons from itself to an oxygen atom. So that Mg and O both achieve noble gas configuration of 2, 8.
6.
Lewis dot shows?
Correct Answer
D. Number of electrons in highest energy shelf
Explanation
The Lewis dot structure is a way to represent the valence electrons of an atom or molecule. It shows the number of electrons in the highest energy level or shell, which is also known as the valence shell. This is important because the valence electrons are the ones involved in chemical bonding and determining the reactivity of an atom. Therefore, knowing the number of electrons in the highest energy shelf helps us understand the chemical behavior and properties of an element.
7.
Select the formula for strontium chloride.
Correct Answer
A. SrCl2
Explanation
The correct formula for strontium chloride is SrCl2. This is because strontium is a group 2 element with a +2 charge, while chloride is a group 17 element with a -1 charge. To balance the charges, two chloride ions are needed for every strontium ion, resulting in the formula SrCl2.
8.
Select the formula for aluminum sulfide.
Correct Answer
C. Al2S3
Explanation
The correct formula for aluminum sulfide is Al2S3. This is because aluminum is a trivalent cation with a charge of +3, and sulfur is a divalent anion with a charge of -2. To balance the charges, two aluminum ions combine with three sulfur ions, resulting in the formula Al2S3.
9.
Element X has an electronic structure 2, 8, 8, 1. Element Y has an electronic structure of 2, 8, 6. What is the chemical formula of the compound formed between X and Y?
Correct Answer
A. X2Y
Explanation
Element X can give away 1 electron each. Y needs to gain 2 electrons. Hence, Y needs 2 of element X. Hence, the formula is X2Y.
10.
Which element, when combined with fluorine, would most likely form an ionic compound?
Correct Answer
B. Lithium
Explanation
Lithium would most likely form an ionic compound when combined with fluorine because lithium is a metal and fluorine is a nonmetal. Metals tend to lose electrons and form positive ions, while nonmetals tend to gain electrons and form negative ions. In the case of lithium and fluorine, lithium would lose one electron to become a positive ion (Li+), and fluorine would gain one electron to become a negative ion (F-). The attraction between these oppositely charged ions would result in the formation of an ionic compound.
11.
Aluminum is a group 3 metal. Which ion does Al typically form?
Correct Answer
C. Al3+
Explanation
Aluminum typically forms the Al3+ ion. This is because aluminum belongs to group 3 in the periodic table, which means it has three valence electrons. In order to achieve a stable electron configuration, aluminum loses all three of its valence electrons, resulting in a 3+ charge. Therefore, the correct ion formed by aluminum is Al3+.
12.
NaCl is an example of the chemical formula of
Correct Answer
C. An ionic compound
Explanation
NaCl is an example of an ionic compound because it is formed by the transfer of electrons between sodium (Na) and chlorine (Cl) atoms. In this compound, sodium loses one electron to become a positively charged ion (Na+), while chlorine gains one electron to become a negatively charged ion (Cl-). The opposite charges of the ions attract each other and form a stable crystal lattice structure, resulting in the formation of NaCl.
13.
Which pair of elements will combine to form an ionic compound?
Correct Answer
B. Fluorine and sodium
Explanation
An ionic compound is formed between a metal and a non-metal.