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Questions in chemistry

[Answered] The periodic table is based on an element's A) molecular mass. B) molecular size. C) atomic number. D) atomic mass.

[Answered] The standard reaction free energy [tex]$\Delta G^0=70 . kJ$[/tex] for this reaction: [tex]$MgCl_2(s)+H_2 O(l) \rightarrow MgO(s)+2 HCl(g)$[/tex] Use this information to complete the table below. Round each of your answers to the nearest kJ. | reaction | [tex]$\Delta G^0$[/tex] | |---|---| | [tex]$MgO (s)+2 HCl (g) \rightarrow MgCl _2(s)+ H _2 O (l)$[/tex] | kJ | | [tex]$\frac{1}{2} MgO ( s )+ HCl ( g ) \rightarrow \frac{1}{2} MgCl _2(s)+\frac{1}{2} H _2 O ( l )$[/tex] | kJ | | [tex]$\frac{1}{4} MgCl _2(s)+\frac{1}{4} H _2 O ( l ) \rightarrow \frac{1}{4} MgO ( s )+\frac{1}{2} HCl ( g )$[/tex] | 18 kJ |

[Answered] The valence of aluminum is +3, and the valence of chlorine is -1. The formula for aluminum chloride is correctly written as A) $ClAl _3$. B) $Cl _3 Al$. C) $Al _3 Cl$. D) $AlCl _3$.

[Answered] Fill in the name and empirical formula of each ionic compound that could be formed from the ions in this table: | cation | anion | empirical formula | name of compound | |---|---|---|---| | [tex]$Mg^{2+}$[/tex] | [tex]$MnO_4^-$[/tex] | | | | [tex]$Cr^{3+}$[/tex] | [tex]$OH^-$[/tex] | | | | [tex]$Ca^{2+}$[/tex] | [tex]$NO_3^-$[/tex] | | |

[Answered] Name the family to which each organic compound belongs. The first answer has been filled in for you. | compound | family | | :---------------- | :----- | | [tex]$CH _3- O - CH _3$[/tex] | ether | | [tex]$CH _3- OH$[/tex] | | | | | | | |

[Answered] What is its noble gas configuration for silicon, Si? A. [Ne] 3s^2 3p^4 B. [Ne] 3s^2 C. [Ne] 3s^2 3p^1 D. [Ne] 3s^2 3p^2

[Answered] The solubility of solid $A$ at $60^{\circ} C$ is $24 g / 100 g$ water. (a) What is the amount of solid required to saturate 30 g of water at $60^{\circ} C$? (b) What will be the amount of saturated solution obtained at $60^{\circ} C$ when 12 the solid $A$ is used to prepare a saturated solution?

[Answered] Potassium and sulfur react to form an ionic compound. What is the correct formula of the compound formed? A. [tex]K _2 S[/tex] B. PS C. [tex]P _2 S_3[/tex] D. [tex]2 K^{+} S ^{2-}[/tex]

[Answered] What mass of NaCl formed when 0.25 g Na react completely with $0.39 g Cl _2$? A. -0.14 g NaCl B. 0.64 g NaCl C. 0.14 g NaCl D. 0.59 g NaCl

[Answered] In which section of a safety data sheet would you find information about the safe handling and storage of a hazardous chemical substance? a) Section 3 b) Section 7 c) Section 14 d) Section 9