Students combine several chemicals and record the observations in their science notebooks. A list of the observed results is given here. • Production of a gas (bubbles) • Phase change (solid to liquid) • A precipitate forms • Change in shape • Crystals dissolving • Heat produced How many of the observations are evidence that a new substance was formed? *
1 point
3
4
5
6

Asample of freon gas has a volume of 2.23 liters, a pressure of 4.85 kpa, and a temperature of -1.36°c. calculate the volume at a pressure of 1.38 kpa and a temperature of 5.5°c. (show work)

Consider the following reaction at equilibrium: c(s)+h2o(g)⇌co(g)+h2(g) predict whether the reaction will shift left, shift right, or remain unchanged upon each of the following disturbances. a) c is added to the reaction mixture. b) h2ois condensed and removed from the reaction mixture c) co is added to the reaction mixture d) h2 is removed from the reaction mixture.

Examine the false statement. compounds are the smallest unit of an element that occur most commonly in nature. select the rewording of the statement that is true. a: atoms are the smallest unit of an element that commonly occur in nature. b: molecules are the smallest unit of an element or compound that commonly occur in nature. c: molecules are the smallest unit of a compound that occur on the periodic table. d: compounds are the smallest unit of an element that occur on the periodic table