Explain the following trend in boiling points: CH4 < C2H6 < C3H8
All molecules are nonpolar = only dispersion forces = increase in mass = stronger dispersion forces = higher BP
Oops!
Check
Okay!
Check
15
State the electron domain, molecular shape, bond angle/s and polarity: H2S
4, bent, 104.5, polar
Oops!
Check
Okay!
Check
monster
Reset all scores!
Oops!
gold
Win 50 points!
Okay!
fairy
Take points!
5
10
15
20
25
baam
Lose 25 points!
Oops!
heart
Other team wins 5 points!
Oops!
shark
Other team loses 10 points!
Okay!
fairy
Take points!
5
10
15
20
25
thief
Give points!
5
10
15
20
25
15
Explain why polar molecules are often soluble in water while non-polar molecules are not. Include discussion on the intermolecular processes involved in dissolving.
soluble = IMF solute and IMF solvent are similar; water is polar = h-bonding and dipole dipole; nonpolar solute = dispersion (way weaker than IMF in solvent)
Oops!
Check
Okay!
Check
banana
Go to last place!
Oops!
rocket
Go to first place!
Okay!
shark
Other team loses 10 points!
Okay!
baam
Lose 25 points!
Oops!
10
Explain why the melting point of HF does not follow the trend of the other hydrogen halides.
HF has hydrogen bonding as its main IMF; while HCl, HBr, HI have dipole-dipole which is a generally weaker IMF than Hydrogen bonding
Oops!
Check
Okay!
Check
10
Give the two common materials used in TLC as the stationary phase
Alumina (Al2O3) and Silica (SiO2)
Oops!
Check
Okay!
Check
15
State the electron domain, molecular shape, bond angle/s and polarity: SO3
3, trigonal planar, 120, non-polar
Oops!
Check
Okay!
Check
15
State the electron domain, molecular shape, bond angle/s and polarity: CH2O
3, trigonal planar, 120, polar
Oops!
Check
Okay!
Check
10
Give an example of a substance that has a very high 1st ionization energy, a very low BP and does not form bonds.
(answers may vary - any noble gas)
Oops!
Check
Okay!
Check
15
State the electron domain, molecular shape, bond angle/s and polarity: [NH4]+
4, tetrahedral, 109.5, non-polar
Oops!
Check
Okay!
Check
15
State the electron domain, molecular shape, bond angle/s and polarity: [CO3]2-
3, trigonal planar, 120, non-polar
Oops!
Check
Okay!
Check
15
Explain why CO is polar while CO2 is nonpolar.
O is more EN than C; CO has uneven distribution of e in bond, thus polar; CO2 is linear (symmetrical), charge distribution is even, thus non-polar
Oops!
Check
Okay!
Check
15
Explain why pure carbon has a melting point of approximately 3550C while pure nitrogen has a melting point of -210C.
Carbon = giant covalent structure = strong bonding; N2 molecule = weak dispersion forces between particles = requires lesser energy to separate them
