Chemistry: Chemical Bonds Flashcards
Compare a cation to an anion
Cation: positivity charged ion
- ex: Ca²⁺
Anion: negatively charged ion
- ex: Cl⁻¹
How do ionic bonds form?
one atom loses electron(s) to another atom, forming a cation/anion that are held together by electrostatic attraction
______ are formed by ionic bonds between _______ and ________
Salts
metal and nonmetal
ionic bond (salts) = metal + nonmetal
How to covalent bonds form?
form when two atoms share one or more pairs of electrons
What is the difference between polar covalent bonds and non polar covalent bonds?
Polar covalent: atoms are shared unequally
- Ex: H2O
Nonpolar covalent: atoms are shared equally
- Ex: CH4, O2
T/F: Ionic bonds are stronger than covalent bonds
False, covalent bonds are stronger than ionic bonds
What causes unequal sharing of electrons in polar covalent bond?
difference in electronegativity between atoms cause unequal sharing of electrons
What type of bond forms between two nonmetals?
covalent bonds
In water, a polar covalent bond forms between Oxygen and Hydrogen. What is the partial charge on the oxygen? What is the partial charge on the hydrogen?
Oxygen: partial negative
Hydrogen: partial positive
How to hydrogen bonds form?
slightly positive Hydrogen in one molecule that is attracted to an electronegative atom
What type of bond forms between water molecules?
Hydrogen bonds
Why do hydrogen bonds form between water molecules?
the partial negative of oxygen in one water molecules is attracted to the partially positive charged hydrogen in another water molecule
Explain how hydrogen bonding causes cohesion in water
Cohesion is the attraction of like molecules to each other. Hydrogen bonding between water molecules causes water to stick to itself. Water is also adhesive (stick to substances that arent itself) because its attracted to opposite charges on surfaces, etc.
Name two factors that affect the size of an atom or the atomic radius
- distance of electron to the proton
- the amount of protons in the nucleus
In regards to ionic radii, know if cations/anions are larger/smaller than their neutral atom. Be able to explain why
cations - smaller, because they have more protons than electrons. increase # of protons allows a stronger force to be pulled on electrons, therefore, decreasing the ionic radii
anions - larger, because they have more electrons than protons, so there is not enough protons to exert a strong enough force to pull the electrons closer to the nucleus. this means the ionic radii increases.
