I can't fully answer this question because it is incomplete. In order for me to help you, I could just define what a precipitation reaction is and give a concrete example.
A precipitation reaction consists of two aqueous solutions that when reacted together, forms an insoluble salt. For example,
AgNO₃ (aq) + HCl (aq) --> AgCl (s) + HNO₃ (aq)
In this case, the precipitate is AgCl, Silver Chloride, which appears as a white solid.
Carbon atomic number ⇒ 6
Carbon mass number ⇒ 12.
Carbon atomic number - Carbon mass number = number of neutrons.
12 - 6 = 6 neutrons.
Proton charge ⇒ +1
The total charge of the nucleus of a carbon atom ⇒⇒⇒ +6.
So the naswer is (3) +6
What of the gasses is N and the flame changes it's color from Orange to blue
Answer:
HCl (aq) + KOH (aq) --------> KCl (aq) + H2O (l) [balanced molecular equation]
Explanation:
Balanced molecular equation has all the components of reaction written as "molecules" thus the name molecular (the other equations break appropriate components into ions, those are total ionic or net ionic equation)
We know hydrochloride acid solution is written as HCl (aq) and potassium hydroxide solution is written as KOH (aq). We know from our knowledge that when acids react with bases they make salt and water, so now we react!
HCl (aq) + KOH (aq) --------> KCl (aq) + H2O (l) [balanced molecular equation]
Answer:

Explanation:
Let's rewrite the given word equation in its chemical balanced equation representation:
1. Lead(II) nitride is represented by lead, Pb, in an oxidation state of 2+, while nitride is a typical nitrogen anion with a state 3-. As a result, the lowest common multiple between 2 and 3 is 6, meaning 2 lead cations are needed to balance 3 nitrogen anions:
.
2. Ammonium sulfate consists of an ammonium cation with a 1+ charge and sulfate anion with a 2- charge, two ammonium cations needed:
.
3. Lead(II) sulfate would have one lead cation and one sulfate anion, as they have the same magnitude of charges with opposite signs:
.
4. Ammonium nitride would require three amonium cations to balance the nitride anion:
.
Let's write the balanced equation:
