Which statement about energy and combustion is accurate? Select one: a. A fuel's potential energy releases during combustion and converts to kinetic energy. b. A fuel's chemical energy is the result of rapid vibrations in the molecules. c. Chemical changes involve an exchange of energy; physical changes involve no energy exchange. d. Chemical and physical changes almost never involve an exchange of energy.

The following reaction is an example of a substitution reaction. $2Na+Cl_{2}\rightarrow 2NaCl$ TRUE FALSE

Part I: Unit Conversions.Show all work (known and unknown, and dimensional analysis - including units! Write your answers in the boxes provided. Unit Test: Dimensional Analysis and Mole Convers 1. Find the number of minutes in 25 years, assuming that $1year=365days$ K:25 years 2. The driving distance from Spokane to Seattle is 479,000 meters. Convert this distance to miles given $1m=100cm,1in=2.54cm,12in=1ft,$ and $1mi=5280ft$ $\square $ Part II: Mole Conversions . Show all work (known and unknown, and dimensional analysis - including units! Write your answers in the boxes provided. 3. A sample contains $9.2\times 10^{22}$ atoms of beryllium (Be)How many moles is this? $\square $ 4. The formula for Aluminum Carbonate is $Al_{2}(CO_{3})_{3}$ What is the molar mass of aluminum carbonate? $\square $

What are some examples of foods that need an emulsifier mayonnaise chocolate ice-cream oil water various salad dressings.

27. The contents of a drum have not been identified. You notice crystalline material on top of the drum, you should treat the contents as: A. shock-sensitive waste. B. nearly empty. C. containing chlorinated solvent. D. containing caustic materials.

Malia was able to make a paperclip float on the surface of water. What will most likely happen to the paperclip if a drop o dishwashing detergent is added near it? Soap is a surfactant that increases the intermolecular forces of water allowing the paperclip to continue to float. Soap makes the water less viscous making the paperclip sink. Soap is a surfactant that disrupts the intermolecular forces of water making the paperclip sink. Soap makes the water more viscous allowing the paperclip to continue to float.

What is the cell potential of an electrochemical cell that has the half-reactions shown below? $Ag^{+}+e^{-}\rightarrow Ag$ $Fe\rightarrow Fe^{3+}+3e^{-}$ Click for a reduction potential chart A. $-0.44$ B. 1.24 V C. 0.44V D. $-1.24V$

An ionic bond is most accurately described as forming through: ) The sharing of electron pairs between two nonmetal atoms. The transfer of electrons from one atom (typically a metal) to another atom (typically a nonmetal)resulting in oppositely charged ions. The delocalization of electrons among many metal atoms.

Name the following compound. 2-ethylhex-1-ene 4-ethylhex-4-ene 3-methylhept-1 -ene

Which option will increase the rate of reaction? removal of one of the reactants decrease the volume of container lower the temperature of reaction reduce the pressure in the container

Which two properties are most useful in distinguishing between galena and halite? 1. cleavage and color 2. luster and color 3. hardness and streak 4. streak and cleavage