Answer:
A. its reactivity
Explanation:
It's reactivity because copper was exposed to air and if it is reactivity it must be exposed to air
The answer is D. (2,2,2,1)
Answer:
it is a pathways by which a chemical substance moves thru biotic and abiotic components of earth. example is the water cycle
Answer:
Percent yield = 79.79 %
Explanation:
Given data:
Mass of Al₂O₃ = 821 g
Mass of Al = 349 g
Percent yield = ?
Solution:
Chemical equation:
2Al₂O₃ + 3C → 4Al + 3CO₂
Number of moles of Al₂O₃:
Number of moles = mass/molar mass
Number of moles = 821 g/ 101.96 g/mol
Number of moles = 8.1 mol
Now we will compare the moles of Al with Al₂O₃.
Al₂O₃ : Al
2 : 4
8.1 : 4/2×8.1 = 16.2 mol
Mass of Al:
Mass = number of moles × molar mass
Mass = 16.2 mol × 27 g/mol
Mass = 437.4 g
Percent yield:
Percent yield = (actual yield / theoretical yield)× 100
Percent yield = (349 g/ 437.4 g) × 100
Percent yield = 79.79 %
An ion is an atom with a different number of electrons than its number of proton, the charge of an ion is not net
need more information to find the charge but it can't be 0 if it is an ion
an ionic bond is when 2 or more ions attract negative and positive