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Questions in chemistry

[Answered] Silica used in the manufacturing of electronics, paints, soaps, and glass does not present a health hazard. A. True B. False

[Answered] Which is the noble gas notation for chlorine? A. [Ne] 4s^2 4p^5 B. [Ne] 3s^2 3p^5 C. [Ne] 3s^2 \cdot 3p^3 D. [Ne] 3p^3 3p^5

[Answered] A chemist fills a reaction vessel with 0.536 g aluminum hydroxide $\left( Al ( OH )_3\right)$ solid, 0.337 M aluminum $\left( Al ^{3+}\right)$ aqueous solution, and 0.196 M hydroxide $\left( OH ^{-}\right)$aqueous solution at a temperature of $25.0^{\circ} C$. Under these conditions, calculate the reaction free energy $\Delta G$ for the following chemical reaction: $Al(OH)_3(s) \rightleftharpoons Al^{3+}(aq)+3 OH^{-}(aq)$ Use the thermodynamic information in the ALEKS Data tab. Round your answer to the nearest kilojoule.

[Answered] The formula for pH is [tex]$pH =-\log \left[ H ^{+}\right]$[/tex], where [tex]$\left[ H ^{+}\right]$[/tex] is the hydrogen ion concentration. The pH of a fruit juice is 3.2. What is the hydrogen ion concentration of the juice? The hydrogen ion concentration [tex]$\left[ H ^{+}\right]$[/tex] is approximately how many moles per liter? (Round to the nearest tenth.)

[Answered] Which of the following is NOT a physical hazard category? A. Flammables B. Explosives C. Toxics D. Reactives E. Corrosives

[Answered] Combustion of glucose ($C_6H_{12}O_6$) is the main source of energy for animal cells: $C_6H_{12}O_6(s) + 6O_2(g) \rightarrow 6CO_2(g) + 6H_2O(l) \quad \Delta \dot{G}_{r \dot{x} n}(37^{\circ}C) = -2872 . kJ$ One of the most important uses to which this energy is put is the assembly of proteins out of amino acid building blocks. The Gibbs free energy of forma one peptide bond, joining one amino acid to another, is $21 kJ / mol$. Suppose some cells are assembling a certain protein made of 23 amino acids. (Note that the number of peptide bonds in the protein will be one less thar number of amino acids.) Calculate the minimum mass of glucose that must be burned to assemble 450. $\mu$mol of this protein. Round your answer to 2 significant digits.

[Answered] The names of the compounds $FeS , NaCl$, and $Al _3 O _2$ all end in the suffix A) -ic. B) -ite. C) -ate. D) -ide.

[Answered] Which of the following is a correct example of properly segregating cylinders? A. Oxygen cylinders stored next to flammable gases B. Full and empty cylinders stored together C. Cylinders stored by their hazard classification D. All of the choices are correct

[Answered] Decide whether each pair of elements in the table below will form an ionic compound. If they will, write the empirical formula of the compound formed in the space provided. | element #1 | element #2 | Forms ionic compound? | empirical formula of ionic compound | |---|---|---|---| | cesium | chlorine | yes | $\square$ | | rubidium | bromine | yes | $\square$ | | sulfur | strontium | yes | $\square$ | | calcium | cesium | yes | $\square$

[Answered] Which substance is a compound? A. water B. gold C. oxygen D. hydrogen