Answer is (b) , because a chemical change happened
Answer:
No.
Explanation:
No. There is 1 atom of Ca on the left and 2 Ca's on the right and 2 OH's on the left and 4 on the right.
The balanced equation is:
4OH- + 2Ca2+ ----> 2Ca(OH)2.
2NaCN(s) + H₂SO₄(aq) --> Na₂SO₄(aq) + 2HCN(g)
The molar ratio between NaCN : HCN is 2:2 or 1:1
Mass of HCN = 16.7 g
Molar mass of HCN = 1 + 12 + 14 = 27 g/mol
Molar mass of NaCN = 49 g/mol
Therefore, the mass of NaCN is
16.7 g of HCN x 49 g/mol of NaCN / 27 g/mol of HCN = 30.3 grams of NaCN
Therefore, 30.3 grams of NaCN gives the lethal dose in the room.