Balance each of the following equations according to the half-reaction method:
(a) zn(s) + no3 −(aq) ⟶ zn2+(aq) + n2 (g) (in acid)
(b) zn(s) + no3 −(aq) ⟶ zn2+(aq) + nh3 (aq) (in base)
(c) cus(s) + no3 −(aq) ⟶ cu2+(aq) + s(s) + no(g) (in acid)
(d) nh3 (aq) + o2 (g) ⟶ no2 (g) (gas phase)
(e) h2 o2 (aq) + mno4 −(aq) ⟶ mn2+(aq) + o2 (g) (in acid)
(f) no2 (g) ⟶ no3 −(aq) + no2 −(aq) (in base)
(g) fe 3+(aq) + i −(aq) ⟶ fe 2+(aq) + i2 (aq)

i don't see a text, but i am gonna assume this *orbit* the curved path, usually elliptical, described by a planet, satellite, spaceship, etc., around a celestial body, as the sun.

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