The balanced equation is:
2NaCl + 2 H2o → 2 NaOH + Cl2 + H2
1- we put 2 NaCl to balance Cl2 on the other side.
2- we put 2 NaOH to balance Na
3- We put 2 H2O to balance H & O on the to sides
There are 5 steps:
1- measure the mass of the container
2- measure the volume of the liquid
3- measure the combined mass of the liquid and the container.
4-determine the mass of the liquid alone
5-divide the mass by the volume.
C of course is the correct
B) Endothermic - It takes in heat and the temperature decreases, therefore becomes cooler.