Predict these reaction products. If a reaction takes place, balance the reaction if needed. If no reaction takes place then write no reaction.

Cu+FeCl3--->CuCl3 + Fe
Double replacement

Al+HBr---->

AgNO3 + KCL--->AgClKnO3
Double replacement

Ba(NO3)2+MgSO4---->BaSO4(s) +Mg(NO3)2(aq)
Double replacement

C8H18+O2

Can you let me know if I'm on track with the ones I did complete and help me with the ones I didn't?

Cu+FeCl3--->CuCl3 + Fe

Double replacement
This reaction will not occur. First, if it did occur it would be a single replacement (you've replaced only one metal) and second, to occur the single element must be ABOVE the ion in the activity series. Cu is below Fe; therefore, no reaction.

Al+HBr----> AlBr3 + H2 and I'll let you balance it. Note that Al is ABOVE the ion (H^+) so a reaction WILL occur.

AgNO3 + KCL--->AgClKnO3
Double replacement
Looks ok if you add a + sign between the products.

Ba(NO3)2+MgSO4---->BaSO4(s) +Mg(NO3)2(aq)
Double replacement
Looks ok to me.

C8H18+O2 ==> CO2 + H2O and I'll let you balance it.

Sure, I'd be happy to help you with your reactions! Let's go through each one step by step:

1. Cu + FeCl3 ---> CuCl3 + Fe (Double Replacement)
First, let's determine if this reaction will occur by checking the solubility rules for the reactants. Copper (Cu) is a transition metal, so it does not typically undergo a double replacement reaction. However, we can still attempt to balance the equation for completeness.
Balanced reaction: 3Cu + 2FeCl3 ---> 3CuCl2 + 2Fe

2. Al + HBr ---> (No Reaction)
Aluminum (Al) is more reactive than hydrogen (H), so it will not displace hydrogen from its compound. As a result, no reaction will occur.

3. AgNO3 + KCl ---> AgCl + KNO3 (Double Replacement)
This is a classic example of a double replacement reaction. Silver nitrate (AgNO3) and potassium chloride (KCl) will exchange ions to form silver chloride (AgCl) and potassium nitrate (KNO3).
Balanced reaction: AgNO3 + KCl ---> AgCl + KNO3

4. Ba(NO3)2 + MgSO4 ---> BaSO4(s) + Mg(NO3)2(aq) (Double Replacement)
The solubility rules indicate that barium sulfate (BaSO4) is insoluble, forming a precipitate. In contrast, magnesium nitrate (Mg(NO3)2) is soluble. Therefore, a double replacement reaction will occur.
Balanced reaction: Ba(NO3)2 + MgSO4 ---> BaSO4 + Mg(NO3)2

5. C8H18 + O2 ---> (Combustion Reaction)
This is a combustion reaction between octane (C8H18) and oxygen (O2). In combustion reactions, hydrocarbons react with oxygen to produce carbon dioxide (CO2) and water (H2O).
Balanced reaction: C8H18 + 12.5O2 ---> 8CO2 + 9H2O

It seems like you are on the right track with most of the reactions. Just keep in mind the solubility rules for double replacement reactions and the general patterns for different types of reactions.