Answer:
-125.4
Explanation:
Target equation is 4C(s) + 5H2(g) = C4H10
These are the data equations for enthalpy of combustion
- C(s) + O2(g) =O2(g) -393.5 kJ/mol * 4
- H2(g) + ½O2(g) =H20(l) = 285.8 kJ/mol * 5
- 2CO2(g) + 3H2O(l) = 13/2O2 (g) + C4H10 - 2877.1 reverse
To get target equation multiply data equation 1 by 4; multiply equation 2 by 5; and reverse equation 3, so...
Calculate 4(-393.5) + 5(-285.8) + 2877.6 and you should get the answer.
Answer:
B
Explanation:
you're moving the decimal 8 spots to the left so it can only be B
1. Both part of the ecosystem
2. There are biotic objects on abiotic objects ( caterpillars on trees ) and abiotic objects on biotic things ( pollen on bees )
3. Both are made of atoms
Answer:
D. period is reciprocal of frequency.
Explanation:
Answer:
B. Secondary pollutant
Explanation:
A primary pollutant is directly emitted into the atmosphere. Volcano eruptions and emissions from cars can result in primary pollutants in the air.
Secondary pollutants are not directly put in the atmosphere. They are created when two or more primary pollutants in the atmosphere react. One example is smog.
Another example is acid rain. If sulphur dioxide, nitrogen dioxide and water react, then acid rain is formed. Therefore, acid rain must be a secondary pollutant.
The best answer choice is B. secondary pollutant
