A catalyst
A catalyst can be in many forms
Answer:
at the beginning:
pH = 0.745
Explanation:
HCl is a strong acid, so:
0.18 M 0.18 0.18.....equilibrium
before base is added:
∴ [ H3O+ ] ≅ <em>C </em>HCl = 0.18 M
⇒ pH = - Log [ H3O+ ] = - Log ( 0.18 )
⇒ pH = 0.745
I disagree, because a physical change changes the form, and a chemical change is a process where one or more substances are altered into new substances.
Answer:

Explanation:
Hello!
In this case, since calcium's oxidation state when forming ionic bonds is +2 and sulfur's oxidation state when bonding those bonds is -2, for the required formula we write:

Now, since they have the same charge number, we infer the ionic compound formed when they bond is calcium sulfide:

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Answer:
What is the total number of valence electrons in the Lewis structure of nh4+?
Total valence electrons pairs
Total electron pairs are determined by dividing the number total valence electrons by two. For, NH4+, Total pairs of electrons are 4.
Explanation:
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