7. Tungsten is a conductor, the rest listed are insulators.
8. Thermal Energy
Answer:
The Empirical Formula.
Explanation:
From the empirical formula and using the weight (in g) of a given substance, we can come up with the molecular formula which is the actual weight of a substance. Sometimes, we find that the empircal formula is the molecular formula.
Explanation:
21. The given molecule for cracking is tetradecane.
On cracking it forms one mole of decane (C10H22) and two moles of ethene gas.
The chemical equation is shown below:

22. The essential condition for the formation of an ester is the reaction of alcohol and acid in presence of concentrated sulfuric acid.
Thus among the given options, the first option is the correct one.
23. Isomers of butanol are shown below:
It is 2-butanol.
The position of -OH group changes to the second carbon.
Answer:
95% Copper and 5% Zinc
Explanation:
Easy stuff read in the chemistry book...
6.02 x 10^23 is Alvogrado's number (Amedio Alvogrado is the name). This formula is determined to find the amount of particles within a substance by a mole.
I hope this helps!