Which equation obeys the law of conservation of mass?
a.
2c4h10 + 2cl2 + 12o2 7co2 + ccl4 + 10h2o
b.
c4h10+ cl2 + 2o2 7co2 + ccl4 + 8h2o
c.
2c4h10+ 2cl2 + 12o2 4co2 + ccl4 + h2o
d.
2c4h10+ 2cl2 + 6o2 co2 + ccl4 + 6h2o
e.
4c4h10+ 4cl2 + 14o2 14co2 + ccl4 + 20h2o

The correct answer for plato/edmentum is A (2C4H10 + 2Cl2 + 12O2 = 7CO2 + CCl4 + 10H2O)

:)

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol