Answer:
Degree of intermolecular hydrogen bonding
Explanation:
The energy required to melt a solid substance and the temperature at which the solid melts depends on the structure of the solid crystal as also on the magnitude of the intermolecular forces present in the solid.
Ice is less dense than liquid water, there are spaces in the crystal structure of ice. Secondly, the magnitude of hydrogen bonding in ice is lower due to lower intermolecular interaction between the water molecules. Given the lower intermolecular interaction in ice, the heat of fusion is much lower since the intermolecular interactions are easier to break.
In liquid water, hydrogen bonding is much stronger and there is greater intermolecular interaction between the water molecules. It takes more energy to break down these intermolecular interactions, hence the high enthalpy of vaporization of liquid water.
Answer:
The third reaction
(2NaOH + NiCL2 ---> 2NaCl + Ni(OH)2)
Explanation:
By definition, a precipitation reaction refers to the formation of an insoluble salt when two solutions containing soluble salts are combined.
(Source: lumenlearning)
From the 4 options, we can eliminate the first and second one immediately because there is no formation of an insoluble salt.
Then, the last one can also be eliminated because even though there is insoluble solid formed, but it is not a salt, and, the reactants are not solutions too. In fact, the last one is a displacement reaction. A more reactive metal displaces a less reactive metal to form an ion.
Since the third reaction matches the definition of precipitation reaction, this is the answer.
The chemical element's atomic radius is measured by the size of its atoms, usually the medium or typical distance between the central nucleus and the surrounding electron shells. As the limit is not a well defined physical entity, different definitions of non-equivalent atomic radius exist.
Hope this helps!
Answer:
option B
Explanation:
A spontaneous reaction drive favorable when enthalpy is decreasing and the entropy is increasing on the system. If that happens the reaction occurs spontaneously
The correct answer is option B, that is, add 1.46 grams of NaCl to 250 milliliters of H₂O.
First there is a need to find the moles of NaCl in 250 ml of 0.10 M NaCl,
Moles of NaCl = molarity × volume = 0.10 M × (250/1000L) = 0.025 mol
The corresponding mass of NaCl is,
Mass of NaCl = moles × molar mass = 0.025 mol × 58.5 g/mol = 1.46 g
Thus, there is a need to dissolve 1.46 grams of NaCl solid into 50 ml of H₂O and dilute to 250 ml.
