CHE 101 Lecture Notes - Lecture 2: International System Of Units, Significant Figures

• School: Quinnipiac University
• Department: Chemistry
• Course: CHE 101
• Professor: Rao Durvasula

Document Summary

The metric system is the standard measurement system in america. The international system of units (si) is the official measurement system in science. The si units of: mass: kg (1000 g=1 kg, temperature: k (kelvin, volume: m3, length: m (100cm=1m) The zeros in 50,000 and 00. 46 are not significant) Significant figures are used to represent the unit in a measured number. Naming the amount of sf"s: 50. 0 = 3 sf"s, 0. 00004 = 1 sf, 2012783= 7 sf"s, 4. 8 x 103 = 2 sf"s, 6,000 = 1 sf, 400. 90= 5 sf"s. Always write a scientific answer with the correct amount of sf"s. Not measured and do not have a limited amount of sf"s. A measured diameter would still need sf correctness. For problems that are simple addition/subtraction of decimals, do not use sf"s. Rather, use the least amount decimal places in the original problem. The correct answer in this case would be .