Q. The smallest unit of matter than can enter into chemical reactions and is not divisible by chemical means is call a(n) ______.
nucleus
atom
element
molecule
compound
Q. What does the nucleus of an atom contain?
Electrons
Protons
Neutrons
Protons and electrons
Protons and neutrons
Q. The atomic weight of an atom is equal to the number of ______ plus the number of _______.
electrons, protons
electrons, neutrons
protons, neutrons
protons, isotopes
isotopes, ions
Q. Which of the following statements is true?
Electrons have a negative charge and equal the number of neutrons.
Electrons have a negative charge and equal the number of protons.
Protons have a positive charge and equal the number of neutrons.
Protons have a positive charge and are responsible for the formation of chemical bonds.
None of the above
Q. In an electrically neutral atom, the number of ______ is equal to the number of _______.
neutrons, electrons
protons, neutrons
protons, electrons
electrons, ions
electrons, isotopes
Q. The carbon atom has an atomic number of 6 and an atomic weight of 12. Therefore, a carbon atom has ______ protons.
2
4
6
8
12
Q. ________ are atoms that have the same number of protons but differ in the number of neutrons.
Emulsifiers
Isotopes
Molecules
Compounds
Salts
Q. The molecule KCl is held together by a(n)______ bond.
ionic
covalent
polar
hydrogen
nonpolar
Q. If an atom either gains or loses an electron, the atom is called a(n) _________.
element
nucleus
molecule
compound
ion
Q. Atoms such as sodium, potassium, calcium, or hydrogen, all lose electrons and become ________.
positively charged
negatively charged
molecules
ions
none of the above
