Two groups complete an experiment requiring the mass measurement to be repeated three times in the experiment. group i selects a single member of the group to measure the mass. group ii allows any person of the group to measure the mass once, so they will be done more quickly. at the end of the experiment, the results for group i are closer to the actual than the results of group ii. explain why this might be.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

A650 ml sodium bromine solution has a bromide ion concentration of 0.245 m. what is the mass (g) of sodium bromide in solution? a) 103.b)0.00155.c)16400.d) 16.4.e) 0.159