Which of the following is NOT a sign of a chemical reaction? absorbing light when chemicals are contacted with each other emission of light when chemicals are contacted with each other All of the above are signs of a chemical reaction. absorbing heat when chemicals are contacted with each other emission of heat when chemicals are contacted with each other

Which of the species below is less basic than acetylide? $CH_{3}MgBr$ $CH_{3}ONa$ $CH_{3}Li$ both A and C all of the above

$CH_{3}-CH_{2}-OH$ Spell out the full name of the compound. $\square $

QUESTION 1 OF 10 When reading a chemical label, it's important to check for what two kinds of hazards? SELECT ALL THAT APPLY health safety storage transportation

3) (4 pts) Give the structures (condensed or line-angle structures) of the isomers of $C_{4}H_{10}$ and name each.

8. Explain the rules used to assign oxidation numbers. __ 9. Why do some elements have multiple oxidation states? __

Which of the following is a possible way to describe the $NO_{2}$ component in the reaction below? $N_{2}(g)+2O_{2}(g)\rightarrow 2NO_{2}(g)$ $1LNO_{2}$ 4 moles NO $NO_{2}$ 2 molecules of $NO_{2}$ 2 atoms $NO_{2}$

Question 1 (1 point) $\underline {\quad }H_{2}+\underline {\quad }Cl_{2}\rightarrow \underline {\quad }HCl$

Which amount of surfactant resulted in the greatest amount of airflow? 2 4 Amounts 2 and 4 gave the same airflow.

What classes can a pure substance be divided into? (Reference p 17 of your textbook.) A Elements and compounds B Electrons and protons C Elements and electrons D Neutrons and protons

When a sample contains a flammable or explosive compound , what special preventive measure may be necessary? Using a special chilled canister to collect the sample Electrically grounding the sample container to prevent a spark Wearing static-free clothing Using a nonmetallic sample container