Classify the two balanced equations representing two chemical reactions 1 Cl2 + 2 NaBr + NaCl + 1 Br2 and 2 NaCl +2 Na + 1 Cl,
O Synthesis & Decomposition
O Synthesis & Double Replacement
O Single Replacement & Double Replacement
O Single Replacement & Decomposition

Single Replacement & Decomposition

Given

Two chemical reactions

1. Cl2 + 2NaBr ⇒2NaCl + Br2

2. 2NaCl ⇒2Na + Cl2

Required

Type of reaction

Solution

Equation 1 : A single replacement reaction is a chemical reaction in which one element replaces the other elements of a compound to produce new elements and compounds

General formula :

A + BC ⇒ AC + B

Equation 2 : the decomposition reaction of a compound into its constituent elements or compounds

General formula :

AB ⇒ A + B

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.