Answer:
a. qm = 627.3 J
b. qw = 627.3 J
c. C₂ = 227.4 J/kg.°C
Explanation:
a.
Since, the calorimeter is completely insulated. Therefore,
Heat Lost by Metal = Heat Gained by water
qm = qw
qm = m₁C₁ΔT₁
where,
qm = heat lost by metal = ?
m₁ = mass of water = (density)(volume) = (1000 kg/m³)(100 mL)(10⁻⁶ m³/1 mL)
m₁ = 0.1 kg
C₁ = specific heat capacity of water = 4182 J/kg.°C
ΔT₁ = Change in Temperature of Water = 19.1°C - 17.6°C = 1.5°C
Therefore,
qm = (0.1 kg)(4182 J/kg.°C)(1.5°C)
<u>qm = 627.3 J</u>
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b.
Since,
qm = qw
<u>qw = 627.3 J</u>
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c.
qm = m₂C₂ΔT₂
where,
m₂ = mass of metal = 38.1 g = 0.0381 kg
C₂ = specific heat capacity of metal = ?
ΔT₂ = Change in Temperature of metal = 90°C - 17.6°C = 72.4°C
Therefore,
627.3 J = (0.0381 kg)(C₂)(72.4°C)
(627.3 J)/(0.0381 kg)(72.4°C) = C₂
<u>C₂ = 227.4 J/kg.°C</u>
Answer:

Explanation:
The quantity of moles of ethanol in the solution is:


The mass and volume of ethanol in the solution are, respectively:




The difference between the total volume of water and ethanol mixed to prepare the solution and the actual volume of solution is:


Answer:
C. Lose three electrons to have a full outer shell
Explanation:
Al is in Group 13 of the Periodic Table, so it has three valence electrons.
It must either lose three electrons or gain five to achieve a stable octet.
It is easier to lose three electrons than it is to gain five, so Al loses three electrons.
D. is wrong, for the same reason.
A. is wrong. If Al lost three electrons, it would be breaking into a stable inner shell.
C. is wrong. Al is a metal, so it will lose electrons in a reaction.
Answer:
Explanation:
use the equation
moles = mass/mr
=19.9/79.5
=0.250moles of CuO
then do the same for
H = 2.02/1
=2.02
so CuO is the limiting reagent because there is less amount of it.
Hope this helps :)