I don't know what your answers were but the more "stuff" there is the more energy it takes to freeze or boil it. Hope this could help
The reaction formula of this is C3H8 + 5O2 --> 3CO2 + 4H2O. The ratio of mole number of C3H8 and O2 is 1:5. 0.025g equals to 0.025/44.1=0.00057 mole. So the mass of O2 is 0.00057*5*32=0.0912 g.
<span>Each mole contains Avagodro's number of atoms i.e. 6.023x10^23, so
3 moles x 6.023x10^23 atoms/mole = 18.069x10^23 atoms = 1.8x19^24 atoms </span>
Molality is the moles of solute per kg of solvent.
Moles of NH₄Cl = 2.4 / (14 + 4 x 1 + 35.5)
= 0.0448 mole
Molality = 0.0448 / (19.4 / 1000)
= 2.31 m
METALS ARE MAGNETIC(and maybe metalloids)