Answer:
45.7kj
Explanation:
To calculates the heats of reaction from heats of formation:
∆Hr=£∆Hp -£∆Hr
= £∆Hch3ChOH - £∆HCh2h2+h20
=(-235.1kj)-(+52.47kj/kg + (-241.8kj/kg)
∆H = 45.71kj/kg
Density is given by mass divided by the volume of a substance.
In this case the mass is 0.794 g and the volume is 0.82 cm ×1.45 cm ×1.25 cm = 1.48625 cm³.
Therefore, density = 0.794/ 1.48625
= 0.5342 g/cm³
Thus, the density of lithium metal is 0.5342 g/cm³