Question

please explain
1) what are the concept of significant figures, measurement, and mole?
2) why is using significant figures a practical method for talking about molar quantities of substances?
3)If a typical postcard is 0.1 mm thick, how tall would a stick of 6.022×10^23 postcard be?

Answer 1

1. the number of important significant no.s to nearest accuracy after the decimal point. measurement is the determination of quantities. and mole is the weight divided by molecular mass of the compound or The mass of substance containing the same number of fundamental units as there are atoms in exactly 12.000 g of ¹²C.

2. because molar quantities of substances have a lot of no.s after the decimal point.and to represent them to the nearest accuracy we shall use significant figures.

3. 6.023 * 10^22 mm thick just multiply both you'll get the answer.