Predict the products of each precipitation reaction. Balance...

Key Concepts

Precipitation Reactions

Precipitation reactions involve the formation of an insoluble solid (precipitate) when two aqueous solutions are mixed. This happens when the combination of ions in solution forms a compound that is not soluble in water. The identification of the precipitate relies on understanding solubility rules for various ionic compounds.

Double Displacement Reactions

Double displacement reactions, also called metathesis reactions, occur when the cations and anions of two ionic compounds exchange partners to form two new compounds. In these reactions, the formation of a precipitate, gas, or weak electrolyte can drive the reaction to completion.

Solubility Rules

Solubility rules are guidelines that help predict the solubility of ionic compounds in water. These rules determine which compounds will remain dissolved and which will form a precipitate by indicating general tendencies and exceptions based on the ions present in the compound.

Balancing Chemical Equations

Balancing chemical equations is the process of adjusting the coefficients of reactants and products in a chemical equation to ensure that the number of atoms for each element is equal on both sides. This adheres to the law of conservation of mass, ensuring that matter is neither created nor destroyed in the reaction.

Net Ionic Equations

Net ionic equations show only those ions and molecules directly involved in the chemical reaction, omitting spectator ions that do not participate. They provide a simplified view of the chemical change, emphasizing the species that actually undergo transformation.

Spectator Ions

Spectator ions are ions that exist in the same form on both the reactant and product sides of a chemical equation. They do not participate in the actual chemical change and are omitted from the net ionic equation to simplify the representation of the reaction.

Transcript

00:02 Hello, in this session we're going to be talking about predicting products for precipitation reactions and writing the net ionic equations for those balanced chemical reactions.

00:12 We will be given reactants with the states.

00:16 Our job will be to, number one, predict products, number two, balance, and number three, write the net ionic equations.

00:25 We've got three of these to do, so let's get started.

00:28 Our first problem set, or our first problem is, lead to nitrate, of course this is aqueous, reacts with potassium bromide, also aqueous.

00:50 We are going to predict products, and then we are going to balance this equation.

00:56 So our products, if you will remember the general format, a -x plus b -y, equals a -y.

01:06 Plus b x let's go ahead and predict our products lead is a and that's lead to y is bromine or the bromide ion this is a negative one this is a plus two so here's our chemical formula and our other product will be b which is potassium and x which is nitrate both potassium and nitrate both potassium and nitrate always our aqueous in our world.

01:44 So i'm going to give this a little a q down here so i don't run out of room.

01:49 Step one, we've written our balanced chemical equation, or we've written our skeleton equation, excuse me, with those substances in them.

02:00 Now we need to balance this equation, and i'm just going to balance this one by inspection, because i'm assuming we all have had lots of practice balancing now.

02:10 And now we have a balanced chemical equation.

02:15 I'll erase some of these things, and there's our balanced chemical equation.

02:21 For the first one of these only, i'm going to do the complete ionic equation, and let me get started with that.

02:29 I'm going to split all of our aqs into their associated cations and anions.

02:34 So i've got pb2 plus, this is an aq, plus 2, n03, minus aq, plus two potassium aq plus two bromids aq plus oh i should have finished here this one is our precipitate i'm sorry about that produces pbbr2s plus i almost made this in one line and then my last portion of my products are 3, a q, and a minus 1 charge.

03:37 We are going to then cross off our spectator ions, which will be this and this.

03:46 Those cross off the two nitrates and the two potassiums also are spectators.

03:53 Our last step is to write our net ionic equation, which is just rewriting what we have left after we cross out our spectators.

04:07 And if we've done it correctly, we will have exactly the right ratios and proportions right there.

04:19 So here's our first problem.

04:22 Done.

04:24 Now, let's start our second problem.

04:28 And for our second problem, we are given calcium nitrate...

Please give Ace some feedback