Which type of reaction is pb(no3)2 + 2hcl → pbcl2 + 2hno3? a. decomposition reaction b. single-replacement reaction c. synthesis reaction d. double-replacement reaction

- D. Double- replacement reaction

Explanations:- In general, the decomposition reactions looks like:

The given reaction looks different than this and so it is not decomposition reaction.

A single-replacement reaction looks like:

Our reaction looks different from this so single-replacement is also not correct.

Synthesis reaction looks exactly opposite to decomposition reaction.

The given reaction is different than this and so it is not synthesis reaction also.

A double-replacement reaction looks like:

In this reaction, the ions are exchanged as could be seen in the general reaction. On reaction side,A is with B and C is with D. On product side, A is with D and C is with B.

The same is happening in the given reaction. Nitrate ion is with lead metal on reactant side and chlorine is with hydrogen, On product side, Chlorine is with lead metal and nitrate ion is with hydrogen. So, ion exchange has taken place here and so this is a double-replacement reaction and choice D is correct.

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.

yes the answer is total mass in unchanged   : )