Answer: The percent of yield is 50.03%.
Explanation:
First, we need to balance the equation:
⇒
We need to remember that the chemical equations are written in moles, so we have to convert the amounts in grams to moles, using the molecular weight of every compound: Al2O3 (101.96 g/mol), Al (29.98 g/mol) and O2 (31.99 g/mol).
In consequence, the amounts in moles of every compound will be:
Now, we have to find out which is the limit reagent or in other words, which of the reagents will be consumed first, taking into account the stoichiometric ratio of the balanced equation:
As you can see, the maximum amount (theoretically) of Al2O3 that can be produced is 0.1665 mol.
Finally, we have to use the yield formula to calculate the percent yield of the reaction:
Therefore, the percent of yield is 50.03%.
Answer is: 89 g of CaCO₃ is <span>equired to prepare 50.0g of CaO.
</span>Chemical reaction: CaCO₃ → CaO + CO₂.
m(CaO) = 50,0 g.
m(CaCO₃) = ?
n(CaO) = m(CaO) ÷ M(CaO).
n(CaO) = 50,0 g ÷ 56 g/mol.
n(CaO) = 0,89 mol.
from reaction: n(CaCO₃) : n(CaO) = 1 : 1.
n(CaCO₃) = n(CaO).
n(CaCO₃) = 0,89 mol.
m(CaCO₃) = m(CaCO₃) · M(CaCO₃).
m(CaCO₃) = 0,89 mol · 100 g/mol
m(CaCO₃) = 89 g.
n - amount of substance.
Complete question :
A jeweler has five rings, each weighing 18 g, made of an alloy of 10% silver and 90% gold. She decides to melt down the rings and add enough silver to reduce the gold content to 75%. How much silver should she add?
Answer:
Kindly check explanation
Explanation:
Given the following :
Weight of each alloy = 18g
Initial % of Silver = 10% = 0.1
Initial % of Gold = 90% = 0.9
New % of gold = 75% = 0.75
Hence, new % of silver will be (1 - 0.75) = 0.25
Let the amount of silver to be added = s
Hence,
Initial gold content = final gold content + added silver
18 * 0.9 = 0.75(18 + s)
16.2 = 13.5 + 0.75s
16. 2 = 13.5 + 0.75s
16.2 - 13.5 = 0.75s
2.7 = 0.75s
s = 2.7 / 0.75
s = 3.6
S = 3.6
Hence the amount of silver needed per ring in other to reduce the gold content = 3.6g
Total for the 5 rings = (3.6 * 5) = 18g
C. would best suit your explanation of evolution
Answer:
Its kinetic energy
Explanation:The dart is in motion because of the potential energy being stored and turned into kinetic energy, plus since the dart is aerodynamic, it would have more speed for it to hit the dart board.