Skip to main content
뒤로

Atoms, Molecules, and Chemical Bonds - Exam 1

컨트롤 버튼이 '내비게이션' 모드로 변경되었습니다.
1/21

이 집합의 용어 (21)

  • What determines the chemical reactivity of an atom?
    The electrons in the outermost or valence shell determine an atom's chemical reactivity.
  • What is the maximum number of electrons in the first three electron shells?
    Shell 1 holds up to 2 electrons, Shell 2 holds up to 8 electrons, and Shell 3 holds up to 8 electrons.
  • When is an atom considered stable?
    An atom is stable when its valence shell is full: 2 electrons in shell 1, 8 in shell 2, and 8 in shell 3.
  • What defines an element?
    The atomic number, which is the number of protons in the nucleus, defines an element.
  • What is the relationship between protons and electrons in a neutral atom?
    In a neutral atom, the number of protons equals the number of electrons.
  • What is the octet rule?
    Atoms tend to gain, lose, or share electrons to have 8 electrons in their valence shell, achieving stability.
  • How do atoms with incomplete outer shells achieve stability?
    They interact by sharing, donating, or receiving electrons, forming chemical bonds.
  • What are the two main types of chemical bonds?
    Ionic bonds (transfer of electrons) and covalent bonds (sharing of electrons).
  • What is an ionic bond?
    A bond formed between ions with full positive or negative charges due to electron transfer.
  • What is a covalent bond?
    A bond where atoms share outer electrons; can be polar (unequal sharing) or nonpolar (equal sharing).
  • What determines if a covalent bond is polar or nonpolar?
    The difference in electronegativity between the two atoms; unequal sharing causes polarity.
  • What is electronegativity?
    The ability of an atom to attract shared electrons in a covalent bond.
  • What atoms are highly electronegative?
    Oxygen and Nitrogen are highly electronegative atoms.
  • What is the charge notation for partial charges in polar covalent bonds?
    Partial positive charge is denoted by δ+ and partial negative charge by δ-.
  • What is the difference between polar covalent and ionic bonds in terms of electron sharing?
    Polar covalent bonds share electrons unequally; ionic bonds transfer electrons completely.
  • What is a redox reaction?
    A reaction involving electron transfer: oxidation is loss of electrons, reduction is gain of electrons.
  • How do you determine the type of bond between two atoms?
    Calculate the difference in electronegativity; small difference = covalent, large difference (>1.7) = ionic.
  • What type of bond is found in hydrochloric acid (HCl) with electronegativities H=2.1 and Cl=3?
    Polar covalent bond, because the electronegativity difference is 0.9.
  • How many bonds can carbon form and why?
    Carbon has 4 valence electrons and forms 4 covalent bonds to complete its octet.
  • What is the significance of the phosphate (P) atom in biology regarding bonding?
    Phosphorus can form 5 bonds biologically, sharing multiple pairs of electrons for stability.
  • What is the structure of a water molecule (H2O)?
    Two hydrogen atoms and one oxygen atom joined by single covalent bonds, forming a polar molecule.