Intermolecular Forces and Physical Properties of Pure Substances

Which has the highest normal freezing point?
a. O2
b. N2
c. H2
d. NH3
Which has the lowest enthalpy of fusion?
a. H2O
b. Li2O
c. HCl
d. HF
Which has the least heat of vaporization?
a. H2Te
b. Xe
c. H2Se
d. H2O
Which has the highest normal boiling point?
a. C2H6
b. NH3
c. Li2O
d. CH4
Which has the smallest vapour pressure at 25°C?
a. O3
b. SiO2
c. CO2
d. H2O

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

In this chemical reaction, 325 grams of barium (ba) react completely. how many moles of lithium (li) are produced?

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.