Answer:
5 × 10⁻³ mol
Step-by-step explanation:
Step 1: Given data
- Volume of HCl solution (V): 25 cm³
- Molar concetration of the HCl solution (C): 0.2 mol/dm³
Step 2: Convert "V" to dm³
We will use the conversion factor 1 dm³ = 1000 cm³.
25 cm³ × 1 dm³/1000 cm³ = 0.025 dm³
Step 3: Calculate the moles of HCl (n)
We will use the definition of molarity.
C = n/V
n = C × V
n = 0.2 mol/dm³ × 0.025 dm³ = 5 × 10⁻³ mol