Answer:
c. Hfus is always negative.
Explanation:
Because energy is released when fusing solids
A reaction is exothermic if Δ<em>H</em> (or
in some textbooks) is negative:
- H₂ + Br → 2 HBr, ΔH < 0.
- CH₄ + 2 O₂ → CO₂ + 2 H₂O, ΔH < 0.
A reaction is endothermic if Δ<em>H</em> is positive:
- 2 NH₃ → N₂ + 3 H₂, ΔH > 0.
- 2 HCl → H₂ + Cl₂ ΔH > 0.
<h3>Explanation</h3>
The enthalpy of a system is the sum of its internal energy. ΔH < 0 indicates that the reactants lose internal energy in the reaction. Energy conserves, and those internal energies must have converted to some other form of energy. They typically end up as thermal energy. The reaction will release heat since it is exothermic.
Similarly, ΔH > 0 indicates that the reactants gains internal energy in the reaction. Energy conserves. As a result, the reaction must have gained energy from its surroundings. The reaction will be endothermic since it absorbs heat.
Answer:

Explanation:
Hello there!
In this case, according to the given chemical reaction, it is possible for us to relate the rate of formation of C and the rate of consumption of B as shown below:

Thus, we solve for the rate of change of B as shown below:

Best regards!
Answer:
The answer is D. have a good day!
Explanation:
Answer:
density, yield strength, elasticity, Ductility, toughness, fatigue limit and corrosion resistance