Answer:
A single bond, but it's also a hydrogen bond.
Explanation:
A hydrogen bond forms when hydrogen bonds to the 3 most electronegative atoms: Oxygen, Nitrogen, or Fluorine.
It's a single bond because hydrogen only has two valence electrons. Therefore, the rest of the electrons are placed around the nitrogen atom.
Answer:
A) at the rod's geometrical center
Explanation:
Let us assume that the rod is replaced by water. And now this water volume is in translational and in rotational equilibrium.
Therefore, a net upward force must have been exerted by the surrounding liquid which acts at the center of mass of the water volume.
This force determines through the geometric center of the column of the cylindrical water
Moreover, the force is also independent of submerged body into it
Hence, the first option is correct
Answer:

Explanation:
Potassium nitrate is a soluble salt which readily dissolves in a polar solvent, such as water. When solid potassium nitrate is dissolved in water, it dissociates into potassium cations and nitrate anions.
Due to the resultant ionic charges, the polar water molecules attract the resultant ions and potassium nitrate ions become hydrated, that is, surrounded by water molecules.
Nitrate, our anion, attracts the partially positive ends of water molecules by attracting them via hydrogen atom.
Potassium, the cation, attracts the partially negative end of water molecules by attracting via oxygen atom.
Answer:
C) It provides a lower activation energy for the reaction is the correct answer.
Explanation:
- A catalyst increases the rate of the chemical reaction by lowering the activation energy for a reaction.
- Catalyst is used to increase the reaction rate, it remains unchanged in the chemical reaction and it does not change the equilibrium constant.
- Activation energy is a minimum amount of energy required to initiate the reaction.
The final temperature = 36 °C
<h3>Further explanation</h3>
The balanced combustion reaction for C₆H₆
2C₆H₆(l)+15O₂(g)⇒ 12CO₂(g)+6H₂O(l) +6542 kJ
MW C₆H₆ : 78.11 g/mol
mol C₆H₆ :

Heat released for 2 mol C₆H₆ =6542 kJ, so for 1 mol

Heat transferred to water :
Q=m.c.ΔT
