(C.7A) Ionic compounds have high melting points because
Question 1 options:
there are no free electrons
ions cannot move out of their crystal lattice
The electronegativity difference is 0
a large amount of energy is needed to break the ionic bonds in the crystal lattice.
The correct answer is: a large amount of energy is needed to break the ionic bonds in the crystal lattice.
Lithium is a metal with an oxidation number of 1+ and oxygen is a nonmetal with an oxidation number of 2-. Which is the best explanation for why the correct chemical formula is Li2O?
Question 3 options:
Oxygen can lose two electrons to complete its valence shell. Lithium has one electron it can add to allow it to have a stable valence shell. One oxygen atom will donate one electron each to two lithium atoms.
Oxygen needs two electrons to complete its valence shell. Lithium has one electron it can donate to allow it to have a stable valence shell. One oxygen atom will take the donated electron from two lithium atoms.
Metals can only react with other metals and nonmetals can only react with other nonmetals, so the chemical formula does not exist.
The correct answer is: Oxygen can lose two electrons to complete its valence shell. Lithium has one electron it can add to allow it to have a stable valence shell. One oxygen atom will donate one electron each to two lithium atoms.
From the list below, which are characteristics of ionic compounds?
Question 5 options:
Cannot conduct electricity when dissolved in water or melted.
Electrons are transferred between atoms to form charged particles.
Electrons are shared between atoms to form a molecular bond.
Electrical conductivity when dissolved in water, or when melted.
Atoms in the compound have different electronegativity values from each other.
Atoms in the compound have similar, or the same, electronegativity values.
The correct options are:
Cannot conduct electricity when dissolved in water or melted.
Electrons are transferred between atoms to form charged particles.
Atoms in the compound have different electronegativity values from each other.
True or False: When the Gupta Empire was in control, this was known as the Golden Age of India because of such achievements in science, engineering, philosophy, art, literature, and astronomy.
Question 1 options:
a) True
b) False
a) True
Which two seafaring nations connected the Mediterranean region together in ancient times?
Question 2 options:
a)
Akkadians and Hittites
b)
Sumerians and Babylonians
c)
Phoenicians and Minoans
d)
Egyptians and Ethiopians
c) Phoenicians and Minoans
Which Ancient Mediterranean culture had developed storage for olive oil, plumbing systems and a series of frescoes?
Question 3 options:
a)
Hebrews
b)
Turks
c)
Romans
d)
Minoans