Molar mass NaCl = 58.44 g/mol
number of moles:
mass NaCl / molar mass
145 / 58.44 => 2.4811 moles of NaCl
Volume = 3.45 L
Therefore :
M = moles / volume in liters:
M = 2.4811 / 3.45
M = 0.719 mol/L⁻¹
hope this helps!
"The reaction will absorb energy" is the best conclusion according to the energy diagram of the chemical reaction.
<u>Option: B</u>
<u>Explanation:</u>
The chemical bonds in the reactions are broken and formed as per process and contributed by three major steps: reactants, transition phase and product formation. Here transition phase is in equilibrium stage drived by activation energy, where bond is partially formed and partially broken, located at higher energy level then the starters.
The reactant's energy level is less relative to the products as seen in the endothermic reactions' energy diagram, which depicts that the products are less balanced than reactants. Here when the reaction is forced to the forward direction, then it direct towards the more unbalance entities. As energy is absorbed in the endothermic reaction from surrounding, thus the enthalpy change (ΔH) for the reaction is positive.
Answer: c. Matter and energy are conserved in chemical reactions.
Explanation:
According to the law of conservation of matter, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side.
For every chemical reaction, the law of conservation of energy is applicable which states that the energy of the system remains conserved. Energy can neither be created nor destroyed. It can be transformed from one form to another.