Answer:
C
Explanation:
If the products have a higher energy level than the reactants then the reaction is endothermic.
In an endothermic reaction, the reaction mixture absorbs heat from the surroundings. Therefore, the products will have a higher energy than the reactants and ΔH will be positive.
In an exothermic reaction, the reaction mixture releases heat to the surroundings. Therefore, the products will have a lower energy than the reactants and ΔH will be negative.
The carbon is considered because it is form by oxygen atoms
Answer:
si
Explanation:
Los catalizadores son sustancias que aceleran una reacción química, proporcionando una ruta alternativa para romper y formar nuevos enlaces entre átomos. Su importancia reside en el hecho de que este nuevo camino requiere menos energía que el original, lo que facilita el proceso.
Explanation:
It is given that volume of 
is 300 mL and molarity is 0.200 M.
Volume of NaCl is 200 mL and molarity is 0.050 M.
The chemical reaction will be as follows.
for 
is given as 
.
As, molarity is number of moles present in liter of solution.
Hence, moles of 
(aq) will be calculated as follows.
moles of (aq) = 
= 0.06 mol
![[Pb^{2+}]](https://tex.z-dn.net/?f=%5BPb%5E%7B2%2B%7D%5D)
= 
= 0.120 M
Mole of 
= 
= 0.010 M
Now, Q = ![[Pb^{2+}][Cl^{-}]^{2}](https://tex.z-dn.net/?f=%5BPb%5E%7B2%2B%7D%5D%5BCl%5E%7B-%7D%5D%5E%7B2%7D)
= 
= 
As, Q < hence, there will be no formation of precipitate.
