Question

A sample of an element has a mass of 80.01g and a density of 2.70 g/cm3. How many significant figures does the mass have?

Answer 1

The mass has 4 significant figures

Further explanation  

Rules for significant numbers

• 1. all non-zero numbers are significant numbers
• 2. a zero which is located between two non-zero numbers including a significant number
• 3. all zeros are located in the final row written behind the decimal point include significant number
• 4. zero decimal point is not significant number

a sample has mass = 80.01 g

a zero which is located between two non-zero numbers including a significant number, so the mass has 4 significant figures : 8,0,0 and 1