Answer:
ones that can be mixed together
Explanation:
like water or ethanol
<span>If thermal energy (heat) must be added to a chemical reaction in order for the reaction to take place, the reaction is endothermic. </span>
Answer:30 L
Explanation:
Initial Volume
=
V
1
=
60
l
i
t
e
r
Initial Temperature
=
T
1
=
546
K
Final Temperature
=
T
2
=
273
K
Final Vloume
=
V
2
=
?
?
Sol:-
Since the pressure is constant and the question is asking about temperature and volume, i.e,
V
1
T
1
=
V
2
T
2
⇒
V
2
=
V
1
⋅
T
2
T
1
=
60
⋅
273
546
=
60
2
=
30
l
i
t
e
r
⇒
V
2
=
30
l
i
t
e
r
Hence the new volume of the gas is
30
l
i
t
e
r
Answer : 0.8663 Kg of chalcopyrite must be mined to obtained 300 g of pure Cu.
Solution : Given,
Mass of Cu = 300 g
Molar mass of Cu = 63.546 g/mole
Molar mass of
= 183.511 g/mole
- First we have to calculate the moles of Cu.

The moles of Cu = 4.7209 moles
From the given chemical formula,
we conclude that the each mole of compound contain one mole of Cu.
So, The moles of Cu = Moles of
= 4.4209 moles
- Now we have to calculate the mass of
.
Mass of
= Moles of
× Molar mass of
= 4.4209 moles × 183.511 g/mole = 866.337 g
Mass of
= 866.337 g = 0.8663 Kg (1 Kg = 1000 g)
Therefore, 0.8663 Kg of chalcopyrite must be mined to obtained 300 g of pure Cu.
Answer:
x = 100 * 1.1897 = 118.97 %, which is > 100 meaning that all of the HClO2 dissociates
Explanation:
Recall that , depression present in freezing point is calculated with the formulae = solute particles Molarity x KF
0.3473 = m * 1.86
Solving, m = 0.187 m
Moles of HClO2 = mass / molar mass = 5.85 / 68.5 = 0.0854 mol
Molality = moles / mass of water in kg = 0.0854 / 1 = 0.0854 m
Initial molality
Assuming that a % x of the solute dissociates, we have the ICE table:
HClO2 H+ + ClO2-
initial concentration: 0.0854 0 0
final concentration: 0.0854(1-x/100) 0.0854x/100 0.0854x / 100
We see that sum of molality of equilibrium mixture = freezing point molality
0.0854( 1 - x/100 + x/100 + x/100) = 0.187
2.1897 = 1 + x / 100
x = 100 * 1.1897 = 118.97 %, which is > 100 meaning that all of the HClO2 dissociates