What is the mass of soot formed during the thermal decomposition of ethane weighing 90 grams. Soot yield 80%.

Let’s implement the solution:
1. In accordance with the condition of the problem, we write the equation:
W = 80%
m = 90 g. X g. -?
C2H6 = 2C + 3H2 – decomposition, obtained carbon (soot), hydrogen;
2. Calculations:
M (C2H6) = 30 g / mol.
M (C) = 12 g / mol.
Y (C2H6) = m / M = 90/30 = 3 mol.
3. Proportion:
3 mol (C2H6) – X mol (C);
-1 mol -2 mol from here, X mol = 3 * 2/1 = 6 mol.
5. Find the mass of the product:
m (C) = Y * M = 12 * 6 = 72 g (theoretical mass)
W = m (practical) / m (theoretical) * 100;
m (practical) = 0.80 * 72 = 57.6 g.
Answer: The mass of soot is 57.6 g.