Taking into account the definition of density, the density of the sample is 0.5 
.
It is necessary yo know that density is defined as the property that matter, whether solid, liquid or gas, has to compress into a given space.
In other words, density allows you to measure the amount of mass in a certain volume of a substance.
Then, the expression for the calculation of density is the quotient between the mass of a body and the volume it occupies:
In this case, you know:
Then, replacing in the definition of density:
Solving:
<u><em>density= 0.5 </em></u><u><em /></u>
Finally, the density of the sample is 0.5 .
Learn more about density:
A) covert 0.330g to moles by dividing by molar mass of P2O5 .. Let's call this Y moles
B) 1 mole of anything contains the Avogradro Number of molecules
So here it is 6.02 x 10^23 x Y molecules
C) work out how many atoms in each molecule 2P + 5O total 7
So multiply answer to B by 7 to get final answer
There’s only one measurement the question doesn’t make sense
Based on the diagram shown, a numerical setup for calculating the gram-formula mass for reactant 1 would be :
6(1) + 2(12) + 16
Hope this helps
Answer:
6.67 moles
Explanation:
Given that:-
Moles of hydrogen gas produced = 10.0 moles
According the reaction shown below:-
3 moles of hydrogen gas are produced when 2 moles of aluminium undergoes reaction.
Also,
1 mole of hydrogen gas are produced when 
moles of aluminium undergoes reaction.
So,
10.0 moles of hydrogen gas are produced when 
moles of aluminium undergoes reaction.
<u>Moles of Al needed = moles = 6.67 moles</u>
