An atom that contains four electrons in its valence shell is capable of forming multiple types of bonds: single bonds, as an atom fitting this description can create four single bonds or a mix of single, double, and triple bonds. Take for instance alkanes, where this atom could form one double bond along with two single bonds, or conversely, two double bonds, which is seen in alkenes. For triple bonds, this atom could make one triple bond and a single bond, as seen in alkynes.
<span>BaCl2 + Na2SO4 --> BaSO4 + 2NaCl
In this reaction, 1.0 g of BaCl2 and 1.0 g of Na2SO4 are present. We need to identify the limiting reactant.
"First, convert grams to moles"
1.0 g BaCl2 * (1 mol BaCl2 / 208.2 g BaCl2) = 4.8 x 10^-3 mol BaCl2
1.0 g Na2SO4 * (1 mol Na2SO4 / 142.04 g Na2SO4) = 7.0 x 10^-3 mol Na2SO4
(7.0 x 10^-3 mol Na2SO4 / 4.8 x 10^-3 mol BaCl2) = 1.5 mol Na2SO4 per mol BaCl2
"Using this ratio to compare with the balanced equation, BaCl2 + Na2SO4 --> BaSO4 + 2NaCl"
The balanced equation indicates that 1 mol of BaCl2 reacts with 1 mol of Na2SO4. However, we found that 1.5 mol of Na2SO4 is available for each mol of BaCl2. Therefore, BaCl2 is the limiting reagent.</span>
