PLS PLS PLS PLS HELP IM STRUGGLING Which of the tests above would provide the most useful information to determine whether the sample is a pure substance or a mixture?

A. 4 only
B. 1 and 4
C. 1,2, and 3
D. 1 only

Of the groups of elements below, which are most likely to gain electrons to become anions? a. alkali metal b. boron group c. halogen d. transition metal

Sulfur dioxide and oxygen react to form sulfur trioxide during one of the key steps in sulfuric acid synthesis. an industrial chemist studying this reaction fills a 25.0l tank with 4.5 mol of sulfur dioxide gas and 4.5 mol of oxygen gas at 30.°c. he then raises the temperature, and when the mixture has come to equilibrium measures the amount of sulfur trioxide gas to be 1.4 mol. calculate the concentration equilibrium constant for the reaction of sulfur dioxide and oxygen at the final temperature of the mixture. round your answer to 2 significant digits.

Consider the story you just read. all but one of the choices below indicate that something is living.