Which of the following are considered pure substances? Select all that apply. Select all that apply: an element a compound a mixture none of the above

2. Can you determine conclusively that an unknown substance contains only magnetite by using only a magnet? Explain your answer. __

Before you go, which type of molecule would you choose to be the anode in a lithium battery? a) The metal with the most negative potential b) It does not matter since lithium's potential is so negative c) The metal with the most positive potential d) Another lithium compound

$2Fe_{2}O_{3}(s)+3C(s)\rightarrow 4Fe(s)+3CO_{2}(g)$ Calculate the mass of iron produced from the complete reaction of 64.0 grams of iron (III)oxide. 89.5 g Fe 22.48 Fe 11.2 g Fe 44.88 Fe 107 g Fe

Problem 19. (1 point) Elements of alkali metal typically are highly reactive bond with two atoms of oxygen form cations with a charge of $+2$ are monatomic gases

QUESTION Q Which of the following is true concerning mass number? ANSWER Using mass number notation, we can identify the number of protons. electrons.and neutrons. Isotopes differ in their numbers of electrons. The mass number is equal to the number of protons. Thus, the mass number of Helium is 2. The mass of electrons contributes significantly to mass number. IDONT KNOWYET

All the elements present in the same group of the periodic table have the same __ number of valence electrons number of energy levels number of electrons number of neutrons

Multiple Choice Question If phenol red is added to a solution with a pH of 9.0, it will appear __ pink-red yellow

Approved laboratory safety glasses must be worn - when lighting a bunsen burner at all times while dispensing liquids while centrifuging liquids Clear my selection

What precipitate forms when mixing silver(I)nitrate and sodium chloride? silver(I) chloride sodium nitrate no precipitate forms

Which of these equations correctly expresses the self-ionization of water? $H_{2}O+H_{3}O^{+}\leftrightarrow H_{2}O+OH^{-}$ $H_{2}O+H_{2}O\leftrightarrow 2OH^{-}$ $H_{2}O+H_{2}O\leftrightarrow 2H_{3}O^{-}$ $H_{2}O+H_{2}O\leftrightarrow H_{3}O^{+}+OH^{-}$