11. A certain gas takes three times as long to effuse out as helium. Its molecular mass will be

(2) 36 u
(1) 27 u
(3) 64 u
(4) 9u

Which of these properties, used alone, would be least useful in identifying most minerals? a. color b. luster c. streak d. density

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

The biosphere of the earth is made up of what compound? organic or inorganic?