The order of placement of the elemnts on the modern Periodic Table is determinated by:
1)atomic number (Z=number of protons).
In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed. The distinction between physical and chemical change is not clear cut.
Answer: 8.30 g of calcium sulfate are produced from 10 grams of lithium sulfate.
Explanation:
To calculate the moles :
According to stoichiometry :
1 mole of 
require = 1 mole of 
Thus 0.061 moles of will require=
of 
Thus is the limiting reagent as it limits the formation of product and is the excess reagent.
As 1 mole of give = 1 mole of 
Thus 0.061 moles of give = of
Mass of 
Thus 8.30 g of calcium sulfate are produced from 10 grams of lithium sulfate.
Answer choice A, B, and C is right about the valence electrons. For answer choice D and E, Would in it be a more of an element kind of choice. whether the element is closer to the left side of the periodic table or not determines the high and low energy.
