Aluminum bromide should be written as AlBr₃ since we are told that there are 3 atoms of Br for every atom of Al.
I hope this helps. Let me know if anything is unclear.
They are about 4.5 billion years old. Hope this helps.
Answer:
Percent yield = 57%
Explanation:
Given data:
Number of moles of propane = 4.50 mol
Number of moles of carbon dioxide = 7.64 mol
Percent yield = ?
Solution:
Chemical equation:
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Now we will compare the moles of propane and carbon dioxide.
C₃H₈ : CO₂
1 ; 3
4.50 : 3×4.50 = 13.5 mol
Percent yield:
Percent yield = actual yield / theoretical yield × 100
Percent yield = 7.64 mol / 13.5 mol × 100
Percent yield = 0.57× 100
Percent yield = 57%
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.