Answer:
2.00 × 10⁻³ g
Explanation:
Step 1: Write the balanced decomposition reaction
2 NaHCO₃ ⇒ Na₂CO₃ + CO₂ + H₂O
Step 2: Calculate the moles corresponding to 0.0118 g of Na₂CO₃
The molar mass of Na₂CO₃ is 105.99 g/mol.
0.0118 g × 1 mol/105.99 g = 1.11 × 10⁻⁴ mol
Step 3: Calculate the moles of H₂O produced with 1.11 × 10⁻⁴ moles of Na₂CO₃
The molar ratio of Na₂CO₃ to H₂O is 1:1. The moles of H₂O produced are 1/1 × 1.11 × 10⁻⁴ mol = 1.11 × 10⁻⁴ mol.
Step 4: Calculate the mass corresponding to 1.11 × 10⁻⁴ moles of H₂O
The molar mass of H₂O is 18.02 g/mol.
1.11 × 10⁻⁴ mol × 18.02 g/mol = 2.00 × 10⁻³ g
Answer: a) 2H2 + O2 --> 2H2O
Explanation: 2 compounds are combining to form a new compound. The others have 2 substances as the end result and synthesis only produces one result (2H2O in this case)
31. B
32. C
33. C
34. C
35. A
36. A
I hope this help!
Recall that 1 gallon = 3.785 L, and 1 L = 1000 mL, so to calculate volume in millilitres, multiply by 3.785 and 1000, resulting in 3785 mL. Next, multiply volume by density to calculate mass (Density = Mass/Volume), so 3785 mL * 1.000 g / mL = 3785 g of water.
