1) The metal which reduces the other compound is the one higher in the reactivity. So in this case it is 
.
2) The substance which brings about reduction while itself getting oxidised (that is losing electrons) is called a reducing agent. Here, $\mathrm{Zn}$ is the reducing agent and reduces Cobalt Oxide to Cobalt while itself getting oxidised to Zinc oxide.
<span>Permeable means that a material is full of tiny, connected airspaces that allows water to seep through it.</span>
The molar mass of aluminum sulftae is 342.14 g/mol.
Since the subscript shows that there are 3 sulfurs within the substance, the total mass of sulfur is 96.21g/mol
Now take the mass of the sulfur and divide it by the molar mass of aluminum sulfate, then multiply by 100:
(96.21/342.15)(100) = 28.1% mass composition of sulfate
Answer:
fat provide 9 calories per gram
