Answer:
T₂ = 19.95°C
Explanation:
From the law of conservation of energy:
where,
mc = mass of copper = 37.2 g
Cc = specific heat of copper = 0.385 J/g.°C
mw = mass of water = 188 g
Cw = specific heat of water = 4.184 J/g.°C
ΔTc = Change in temperature of copper = 99.8°C - T₂
ΔTw = Change in temperature of water = T₂ - 18.5°C
T₂ = Final Temperature at Equilibrium = ?
Therefore,
<u>T₂ = 19.95°C</u>
Answer is: 315,29 grams of copper ore.
m(<span>chalcopyrite) = ?
</span>ω(CuFeS₂) = 55,0 % = 0,55.
<span>m(Cu) = 60,0 g.
mass percentage of copper in </span>CuFeS₂:
ω(Cu) = Ar(Cu) ÷ Mr(CuFeS₂).
ω(Cu) = 63,55 ÷ 183,4.
ω(Cu) = 0,346 = 34,6 %.
mass percentage of copper in chalcopyrite:
ω(Cu) : ω₁(Cu) = 100% : ω(CuFeS₂).
ω₁(Cu) = 19,03 % = 0,1903.
m(chalcopyrite) = 60,0 g ÷ 0,1903.
m(chalcopyrite) = 315,29 g.
Answer:
60.88%
Explanation:
The <em>formula for cerium carbonate</em> is Ce₂(CO₃)₃.
Let's <u>assume we have 1 mol of cerium carbonate</u>. The total mass would be equal to the molar mass of Ce₂(CO₃)₃, 460.25 g/mol.
Out of those 460.25 g, the mass <u>corresponding to cerium would be</u>:
- 2 * Molar mass of Ce = 2 * 140.11 g/mol = 280.22 g
Now we can <u>calculate the percentage by mass of cerium</u>:
- % mass = 280.22 / 460.25 * 100% = 60.88%
The general formula for a decomposition reaction is shown as option C. AB -> A + B. This type of reaction is simply when a complex compound and or substance is broken down to form its substituent atoms of their respective elements. It is energy releasing as compounds are broken down and is the inverse of a synthesis type of chemical reaction.
