<u>Answer:</u> The density of phosphorus is 
<u>Explanation:</u>
To calculate the density of phosphorus, we use the equation:
where,
= density
Z = number of atom in unit cell = 1 (CCP)
M = atomic mass of phosphorus = 31 g/mol
= Avogadro's number = 
a = edge length of unit cell = 
(Conversion factor: 
)
Putting values in above equation, we get:
Hence, the density of phosphorus is
Answer:
I think A should be the answer because oxygen is the chemical change of carbon.
Answer:
520 kg
Explanation:
Let's consider the combustion of isooctane.
C₈H₁₈(l) + 12.5 O₂(g) → 8 CO₂(g) + 9 H₂O(l)
We can establish the following relations:
- 1 mL of C₈H₁₈ has a mass of 0.690 g (ρ = 0.690 g/mL).
- The molar mass of C₈H₁₈ is 114.22 g/mol.
- The molar ratio of C₈H₁₈ to O₂ is 1:12.5.
- The mole fraction of O₂ in air is 0.21.
- The molar mass of air is 28.96 g/mol.
50 L of isooctane require the following mass of air.
Answer:
It is valid because his experiment had clear variables.
Explanation:
He had clear variables and did everyhting the same for both plants, even though he had calcium in one and not in the other, which gives him a true and good result.
