Niobium-91 has a half-life of 680 years. after 2,040 years, how much niobium-91 will remain from a 300.0-g sample? 3 g 18.75 g 37.5 g 100.0 g

40dm3 of gas at 760 torr are heated from 5°c to 50°c what is the new volume

Which statement best describes the liquid state of matter? a. it has definite shape but indefinite volume. b. it has definite shape and definite volume. c. it has indefinite shape and indefinite volume. d. it has indefinite shape but definite volume.

An atom that gains or loses one or more electrons is called a(n)