How is the Unit of Quantity of Matter used in Chemistry defined? Calculate the molar mass of: Pb (Cr O3) 2 From the concept of mole indicated, perform the following calculations:
1. What is the mass of a molecule?
2. How many atoms does a molecule of the indicated substance have?
3. In a kilogram of substance, how many molecules will there be?
4. How many moles of atoms of each species are in one mole of molecules?

sorry idk the answer well to you i have a explaination

explanation: a formula which shows the arrangement of atoms in the molecule of a compound

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

6.4 cm (max) - 25 cm (min)

what is the question?