Answer:The correct answer is option C.
Explanation;
Water has unique property that is, it expands on freezing.Which is the reason for less density of ice than water. The cracking of the bottle was due to the expansion of water (present inside the bottle) on freezing.
Generally, density is inversely proportional to the volume of the substance.


As we know ,that water expands on freezing which means that volume increases. And with increase in volume of density decreases.
Hence, the correct answer is option C.
Answer:

Explanation:
= Initial volume = 100 mL
= Final volume = 1000 mL
= Initial concentration = 0.5 M
= Final concentration
We have the relation

The new concentration is
.
Answer:
2.232 g/L
Explanation:
Assuming 1 mol, volume at STP is 22.4 L so you simply divide 50g by 22.4 L to get density
We can use the combined gas law equation to solve for the initial volume

parameters for the first instance are on the left side and parameters for the second instance are on the right side of the equation
substituting the values in the equation

V = 8.50 L
the initial volume is 8.50 L
Answer : The total change in enthalpy of this reaction is 25 kJ.
Explanation :
Enthalpy of reaction : It is defined as the changes in heat energy takes place when reactants go to products. It is denotes as .
ΔH = Energy of product - Energy of reactant
ΔH is positive when heat is absorbed and the reaction is endothermic.
ΔH is negative when heat is released and the reaction is exothermic.
In the given potential energy diagram, the energy of product at higher level and energy of reactant at lower level. The ΔH for this reaction will be positive.
Given:
Energy of product = 55 kJ
Energy of reactant = 30 kJ
ΔH = Energy of product - Energy of reactant
ΔH = 55 kJ - 30 kJ
ΔH = 25 kJ
Thus, the total change in enthalpy of this reaction is 25 kJ.