Answer:
The answer to your question is given below
Explanation:
1. C. 2NaCl + I2 —> 2NaI + Cl2 => C. Single displacement.
From the above equation, we can see that I2 replaces Cl in NaCl to produce NaI. This is simply called a single displacement reaction.
2. E. 2C4H10 + 13O2 —> 8CO2 + 10H2O => E. Combustion.
The above equation shows the burning of Hydrocarbon in the presence of O2. This is simply called Combustion as CO2 and H2O is produced.
3. D 2H2O —> 2H2 + O2 => D. Decomposition.
From the above equation, we can see that a single compound H2O produces two elements H2 and O2. This is simply called a decomposition reaction.
4. A. ZnS + 2HCl —> ZnCl2 + H2S => A. Double Decomposition.
From the above equation, we can see that Cl replaces S in ZnS to produce ZnCl2 and S replaces Cl in HCl to produce H2S. This is simply called double displacement reaction.
5. B. H2 + Br2 —> 2HBr => B. Synthesis.
From the above equation, we can see that two element H2 and Br2 combine to produce a single compound HBr. This is simply called a synthesis reaction.
Example :

If you use the subscript (aq) (=aquaris) , this means that the substance is in a solution.
Subscripts:
-aq-this means that the substance is in a solution
-s-this means that the substance is a solid(or precipitate)
-l-this means that the substance is a liquid
-g-this means that the subtance is a gas
Buffers - mixtures of conjugate acid and conjugate base at ±1 pH unit from pH = pKa. Resistant to changes in pH in response to small additions of H+ or OH-. ... Polyprotic acids - dissociation of each H+ can be treated separately if the pKa values are different
There are 207405.111 grams in that many pounds.