Please help, just help me please 35. Elemental phosphorus burns in oxygen with an intense flame, producing a brilliant light and clouds of the oxide product. These properties of the combustion of phosphor led to its being used in bombs and incendiary de warfare. P4(s) + 502(8) --> 2P205(s) If 4.95 g of phosphorus is burned, what mass of sy it combine with?

I'm gonna assume you want to find how much mass of oxygen 4.95g of phosphorus reacts with

P4(s) + 502(8) --> 2P205(s)

We know that Phosphorus is polyatomic and Oxygen Gas is diatomic

Atomic mass of Phosphorus= 30.97g/mol

Atomic mass for Oxygen = 16g

4 * 30.97 = 123.88g

2 * 16 = 32g

Since there are 5 moles of oxygen: 5 * 32 = 160g

Ok, so 160g of oxygen will react 123.88g of Phosphorus

4.95g phosphorus burns with how much oxygen?

4.95 * 160g

 123.88g

= 6.4g of Oxygen

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.

a corroding iron, if that's one of your choices