7.91 g/ml is the density of the iron piece of 28.5 gms.
Explanation:
The density of a substance is defined as the volume it occupies. It tells the matter present in a substance.
The density is mass per unit volume and is denoted by p.
The formula for density is given by:
density (p) = 
Data given is :
mass= 28.5 grams
V1 = 45.5 ml
V2= 49.1 ml
The initial volume of water was 45.5 ml, when iron piece of 28.5 grams was added the final volume was 49.1 ml.
Putting the values in the equation of density
p = 
p = 7.91 g/ml
Since iron is a dense material it will occupy less volume
Answer:
I(Br)
Explanation:
You will be combining one iodine atom with one bromine atom.
Answer:
3.8 x 10²⁴molecules
Explanation:
Given parameters:
Number of moles = 6.32moles
Unknown:
Number of molecules = ?
Solution:
The number of moles can be used to derive the number of molecules found within a substance.
Now,
1 mole of substance contains 6.02 x 10²³ molecules
6.32 mole of PBr₃ will contain 6.32 x 6.02 x 10²³ = 3.8 x 10²⁴molecules
Answer:
1: due to difference in reactivity and melting point
2 during the reaction both combine with oxygen in this case magnesium remain solid but some potassium vaporise
