When the reactive alkali metal sodium is reacted with poisonous chlorine gas, sodium chloride or table salt is produced. Is mass conserved? Design a simple experiment to support your answer.

Yes, Mass is conserved.

Explanation:

Every chemical reactions obey the law of conservation of mass. The law of conservation of mass states that in chemical reactions, mass is always constant.

Equation:

2Na + Cl₂ → 2NaCl

From the equation above, one can observe that the reaction started using 2 atoms of Na and it produced 2 atoms of the same element in NaCl. A molecule of Cl produced 2 atoms of Cl in the NaCl

Design a simple experiment to support your answer:

Aim: To demonstrate the law of conservation of mass

One Na atom weighs 23g

Two Na atom will weigh 2 x 23 = 46g

1 atom of Cl is 35.5g

1 molecule of Cl containing two atoms of Cl will weigh 2 x 35.5 = 71g

Total mass of reactants = mass of 2Na + 1Cl₂ = (46 + 71) g = 117g

On the product side, Mass of 1 NaCl = 23 + 35.5 = 58.5g

Two moles of NaCl will give 2 x 58.5g = 117g

Since the mass on both side is the same, one can say mass is conserved.