Answer:
evaporation means the state of the water went from liquid to gas which is a physical change. the sugar is still in the beaker which means its chemical properties did not change.
Explanation:
Answer:
Due to hydrogen bond in propylamine.
Explanation:
The boiling point or melting point are property of
a) size
b) the intermolecular force of interactions.
As we know that primary and secondary amines form intermoleclar hydrogen bonds, which increases the force of attractions between molecules increasing the boiling point of amines.
However in case of tertiary amines there is no hydrogen directly attached to electronegative nitrogen atoms, thus no possibility of formation of hydrogen bond hence low boiling points.
The structures are shown in the figure.
Heavy water contains 20% hydrogen by mass and 80% oxygen by mass.
<h3>What is the molar mass of heavy water?</h3>
Heavy water is water which contains the heavy isotope of hydrogen, Hydrogen-2 in its molecules.
The mass of heavy water is greater than that of water.
The molar mass of heavy water is 20.0 g
The percentage composition of the elements in heavy water are as follows:
Hydrogen = 2 × 2g/20 g ×100% = 20%
Oxygen = 16g/20g × 100% = 80%.
Therefore, Heavy water contains 20% hydrogen by mass and 80% oxygen by mass.
Learn more about heavy water at: brainly.com/question/2142633
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Answer:
-162,5 kJ/mol
Explanation:
Cl(g) + 2O2(g) --> ClO(g) + O3(g) ΔH = 122.8 kJ/mol (as we used the reaction in the opposite direction, it will turn the enthalpy from exothermic to endothermic)
2O3(g) --> 3O2(g) ΔH = -285.3 kJ/mol
Cl(g) + O2(g) --> ClO(g) + O3(g) ΔH = 122.8 kJ
+ 2O3 (g) --> 3O2(g) ΔH = - 285.3 kJ
O3(g) + Cl(g) --> ClO(g) + 2O2(g) ΔH = 122.8 + (-285.3) = -162,5 kJ
Answer: Q=mcΔT
Explanation:
c ethyl alcohol = 2400 J/(kg*K)
T boil ethyl alcohol = 78 C = 351 K
T starting = 17 C = 290 K
m=Q/(c*ΔT)
m= (2400 J)/[(2400 J/kg*K)(351 K -290 K)]
= 0.0028g
