they have many carbon-hydrogen bonds that store a great deal of energy. the bonds are easily broken, and the energy can be captured by organisms.
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survival of the fittest
note that density is equal to mass divided by volume.: d=m/v.
using this, we can find the answer to 5.a1.; 11.85/15=0.79.g/ml
5.a2. ethyl alcohol.
5.b1: first subtract to the total mass by the mass of the beaker. 94-30=64g.
5.b2: using the d=mv formula, 64/40=1.6g/ml
5.b3: the liquid is carbon tetra-chloride
5.c1: the volume is 67-50=17ml.
5.c2: d=m/v 192/17=11.3g so, the solid is lead.
5.c3: did that : p
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