Answer:
Two, KCl and PbCl₂.
Explanation:
Hello!
In this case, since the addition of chloride ions promote the following three ionic reactions:

We can infer that both silver chloride and lead (II) chloride are precipitated products as their Ksp are 6.56x10⁻⁴ and 1.59x10⁻⁵ respectively, which means they are merely soluble in water.
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Answer:
c
Explanation:
Nh4OH + HCL ---> NH4Cl + H3O
so ph decreases as H3O increases
and OH also decreases
Answer:

Explanation:
Hello,
In this case, since a change in science is widely known to be considered as a subtraction between the the final and initial values of two measured variables and is represented via Δ, here the final density is 5.43 g/mL and the initial one was 3.21 g/mL, therefore, the change in density is:

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