D. quantitative data can be recorded.
Models help us better understand the phenomena
Answer:
One change of state happens when you add energy to the substance. This change of state is called melting. By adding energy to the molecules in a solid the molecules begin to move quicker and can break away from the other molecules. ... The temperature at which a substance goes from a solid to a liquid is it melting point.
Answer:
Option D) Compound B may have a lower molecular weight.
Explanation:
Compound A and B are standing at the same temperature yet compound A is evaporating more slowly than compound B.
This simply indicates that compound B have a lower molecular weight than compound A.
This can further be seen when gasoline and kerosene are placed under same temperature. The gasoline will evaporate faster than kerosene because the molecular weight of the gasoline is low when compared to that of the kerosene.
Get to know first how many moles in the gas:n = pV/RT= (1.013*10^5*750/760) Pa *1.49*10^-3 m^3/(8.314 J/(molK)*298) n = 0.0601 moles.
The combustion energies are 889 kJ/mol (methane) and 2 220 kJ (propane) x = moles methane, y = moles propane
x*889 + y*2220 = 778 x + y = 0.0601----------- x = 0.267784 moles = 0.267784*100/0.0601 = 44.6 % y = 0.243216 moles = 0.243216*100/0.0601 = 55.4 %
