Which of the following contribute(s) to most of the mass of an atom?
Question 6 options:
A)
Neutrons only
B)
Protons and neutrons
C)
Protons and electrons
D)
Protons only
Question 7 (5 points)
In a certain chemical reaction, the bonds of the products contain more energy than the bonds of the reactants. For the reaction to occur, which of the following best describes what occurred?
Question 7 options:
A)
Energy was released, so the reaction is endothermic.
B)
Energy was released, so the reaction is exothermic.
C)
Energy was added, so the reaction is endothermic.
D)
Energy was added, so the reaction is exothermic
Question 8 (5 points)
A solution
Question 8 options:
A)
is a single-phase homogeneous mixture.
B)
must contain water.
C)
is always a liquid.
D)
can contain more than two phases.
Question 9 (5 points)
Which of the following is true of alloys?
Question 9 options:
A)
They can only be composed of metals.
B)
They must be held together by chemical bonds.
C)
They're liquid solutions.
D)
They must contain a metal.
Question 10 (5 points)
Which of the following best describes an atomic number? An element's identity is defined by its atomic number; this means it represents the number of
Question 10 options:
A)
electrons in the element.
B)
neutrons in its nucleus.
C)
protons plus neutrons in its nucleus.
D)
protons in its nucleus.