Answer:
D
Explanation: An exothermic change is Because it has heat.
Answer:
Cl⁻, Na⁺, OH⁻
Explanation:
The titration is:
CuCl₂(aq) + 2 NaOH(aq) → Cu(OH)₂(s) + 2 NaCl(aq)
In solution, before the reaction, the ions are Cu²⁺ and Cl⁻. The addition of NaOH (Na⁺ + OH⁻) produce the precipitation of Cu²⁺ forming Cu(OH)₂(s). When you reach the equivalence point, there is no Cu²⁺ because precipitates completely. All OH⁻ ions reacts when are added but when Cu²⁺ is finished, excess OH⁻ ions still in solution helping to detect the equivalence point.
Thus, ions present after the equivalence point are:<em> Cl⁻, Na⁺</em> (Don't react, spectator ions), and <em>OH⁻</em>.
Answer:
#2.
Explanation:
Look at the charges. Both are positive, therefore both are cations.
Answer:
It is due to the nature of the reactants
Explanation:
To ignite a solid, we require more heat component compared to liquids and gases. For ignition to occur, oxygen gas combines with a reactant in most cases.
Some factors affect the rate rate at which a chemical proceeds. One of the factors is the nature of reactants.
The solid phase is very slow while the gaseous phase is rapid and fast.
solid phase < liquid phase < gas phase
Gases are free and the molecules move in all direction. They easily combine and react very fast.
