Chem Lab

2 Pages 614 Words

Mole and Mass Relationships
NaHCO3(s) + HCl(aq) ® NaCl(aq) + CO2 + H2O(g)

Purpose
The purpose of the lab was to relate the mass of a product occurring from a chemical equation to that of the mass which was originally predicted through calculation. It was also to learn and understand mole-mass relationships which exist in a chemical reaction and to interpret a balanced chemical equation.

Materials and Equipment
6 M Hydrochloric acid (HCL) Burner
Sodium Hydrogen Carbonate (NaHCO3) Ring Stand
Test Tube (13 x 100mm) Iron Ring
Dropper Pipet Wire Gauze
Evaporating Dish Watch Glass
Microspatula Balance

Procedure
(record all data to table)
1. a) Clean and flame dry an evaporating dish and allow to cool.
b) Find the combined mass of the evaporating dish and watch glass (mass a).
2. Measure 2.50 g of sodium hydrogen carbonate (NaHCO3) to the evaporating dish, while the dish is remaining on the balance (mass b).
3. Set up the ring stand. Place the evaporating dish upon the wire gauze. Then place the watch glass on top of the evaporating dish.
4. a) In a test tube, obtain about 5mL of 6M Hydrochloric acid (HCL). (Use with caution)
b) Using a dropper pipet, a few drops at a time, drop the HCL into the NaHCO3.
c) Add acid until all bubbling ceases.
5. a) Remove watch glass and heat the dish gently, until almost all the liquid is gone. (Avoid spattering)
b) Replace watch glass, allowing a small opening for vapor and gently heat until all liquid evaporates.
6. Find mass of evaporating dish, watch glass and remaining NaCl together (mass c).

Data
a) evaporating dish + watch glass 49.10 g .
b) evaporating dish + watch glass + NaHCO3 51.60 g .
c) evaporating dish + watch glass + NaCl 50.84 g .
Mass of NaHCO3 reactant (b-a) 51.60g - 49.10g = 2.50g
Mass of NaCl product (c-a) 50.84g - 49.10g = 1.74g
Questions
NaHCO3(s) + HCl(aq) ® NaCl(aq) + CO2 + H2O(g)
84g + 36g ®...