CHEM 120 Week 8 Final Exam Review
Course Number:CHEM120
Course Title:Introduction to General,Organic & Biological Chemistry with Lab
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, CHEM 120: Final Review
1. Question: Know what is the atomic number, atomic mass, protons, neutrons &
electrons
Atomic number – is the number of protons in the nucleus of an atom of any
element
Atomic mass – is expressed in amu; is the wighted average
Protons – are positively charged particles in the nucleus
Neutron – are neutral, have no electrical charge
Electrons – are negatively charged particles in the nucleus
Atomic number = number of protons
Atomic number – (minus) atomic mass = neutrons
2. Question: Describe the shapes of molecules H2S, CBr4, & PCl3
H2S – bent
Number of bonded atoms: 2
Number of lone pairs: 2
Number of electron sets: 4
CBr4 – tetrahedral
Number of bonded atoms: 4
Number of lone pairs: 0
Number of electron sets: 4
PCl3 – pyramidal
Number of bonded atoms: 3
Number of lone pairs: 1
Number of electron sets: 4
3. Question: Calculating types of bonding (ionic, covalent, nonpolar covalent)
Subtract the smaller EN value from the larger EN value
0 – 0.4 = nonpolar covalent
> (greater than) 0.4 – 1.7 = polar covalent
> (greater than) 1.7 = ionic bond
Ionic bonds – is a bond that forms when electrons is being transferred from one form to
another form, which results in positive & negative ions
Covalent bond – a bond formed when atoms share electrons
Nonpolar covalent bonds – when the EN is very similar between 2 atoms
Polar covalent – when the EN is different between 2 atoms
4. Question: Non – polar covalent bonds & polar covalent bonds & electron sharing
Bonding electron pair – the shared pair of electrons in covalent bonds
Course Number:CHEM120
Course Title:Introduction to General,Organic & Biological Chemistry with Lab
Well Explained Answers
Secure high grade
Best feedback (rated) document by students
, CHEM 120: Final Review
1. Question: Know what is the atomic number, atomic mass, protons, neutrons &
electrons
Atomic number – is the number of protons in the nucleus of an atom of any
element
Atomic mass – is expressed in amu; is the wighted average
Protons – are positively charged particles in the nucleus
Neutron – are neutral, have no electrical charge
Electrons – are negatively charged particles in the nucleus
Atomic number = number of protons
Atomic number – (minus) atomic mass = neutrons
2. Question: Describe the shapes of molecules H2S, CBr4, & PCl3
H2S – bent
Number of bonded atoms: 2
Number of lone pairs: 2
Number of electron sets: 4
CBr4 – tetrahedral
Number of bonded atoms: 4
Number of lone pairs: 0
Number of electron sets: 4
PCl3 – pyramidal
Number of bonded atoms: 3
Number of lone pairs: 1
Number of electron sets: 4
3. Question: Calculating types of bonding (ionic, covalent, nonpolar covalent)
Subtract the smaller EN value from the larger EN value
0 – 0.4 = nonpolar covalent
> (greater than) 0.4 – 1.7 = polar covalent
> (greater than) 1.7 = ionic bond
Ionic bonds – is a bond that forms when electrons is being transferred from one form to
another form, which results in positive & negative ions
Covalent bond – a bond formed when atoms share electrons
Nonpolar covalent bonds – when the EN is very similar between 2 atoms
Polar covalent – when the EN is different between 2 atoms
4. Question: Non – polar covalent bonds & polar covalent bonds & electron sharing
Bonding electron pair – the shared pair of electrons in covalent bonds
