Express 0.00250 L in scientific notation.

• A. 2.50×10^-4 L
• B. 2.50×10^-3 L
• C. 25.0×10^-3 L
• D. 0.250×10^-2 L

Answer: (B)

Write the number as a product of a value between 1 and 10 and a power of ten. Move the decimal point in 0.00250 L three places to the right to get 2.50. Because the decimal was moved to the right, the exponent is negative, giving 2.50 × 10^-3 L. The trailing zero after the 5 is significant, so we keep it to show three significant figures, matching the original value. Forms that push the coefficient outside 1–10 or change the magnitude aren’t the standard scientific notation for this value, even though they might be mathematically equivalent.