Zn + 2hcl → zncl2 + h2
at conditions of standard temperature and pressure, determine how many liters of hydrogen gas are produced by placing a zinc nail with a mass of 2.2g into an excess of hydrochloric acid.
a) 0.0015l
b) 0.75l
c) 1.33l
d) 6.42l

0.75

Explanation:

0.75L To determine this, set up the following stoichiometry problem:

2.2gZn x

1molZn

65.41gZn

x

1molH2

1molZn

x

22.4LH2

1molH2

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.

43.452

step-by-step explanation:

284 times .153 = 43.452