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Questions in chemistry

[Answered] An organic chemist measures the temperature [tex]$T$[/tex] of a solution in a reaction flask. Here is the result: [tex]$T=32.394^{\circ} C$[/tex] Convert [tex]$T$[/tex] to SI units. Round your answer to 6 significant figures.

[Answered] Fill in the gaps to balance the equation. Use the smallest set of whole numbers to balance the equation and include coefficients of "1" when appropriate. [tex]$\square$ $C _6 H _{12} O _6+$ $\square$ $O _2 \rightarrow$ $\square$ $CO _2+$ $\square$ $H _2 O$[/tex] Complete the table to determine how many atoms of each element are present in the reactants and products. | Element | Reactant | Products | | :------ | :------- | :------- | | C | | | | H | | | | O | | |

[Answered] Which of these changes is an example of a chemical change? A. sodium making an explosion when added to water B. solid CO₂ turning into gaseous CO₂ C. water droplets forming outside a glass on a hot day D. evaporation of water from a pan

[Answered] Fill in the gaps to balance the equation. Use the smallest set of whole numbers to balance the equation and include coefficients of "1" when appropriate. [tex]$\square$ LiOH + $\square$ ZnCl _2 \rightarrow $\square$ LiCl + $\square$ Zn ( OH )_2[/tex] Complete the table to determine how many atoms of each element are present in the reactants and products. | Element | Reactant | Products | |---|---|---| | Li | $\square$ | $\square$ | | O | $\square$ | $\square$ | | H | $\square$ | $\square$ | | Zn | $\square$ | $\square$ | | Cl | $\square$ | $\square$ |

[Answered] Why study chemistry? a) to be better informed about the world b) to be better able to make informed decisions c) to learn a technique for identifying and solving problems d) all of the above

[Answered] Fill in the gaps to balance the equation. Use the smallest set of whole numbers to balance the equation and include coefficients of "1" when appropriate. [tex]$\square$ Ca ( OH )_2+ $\square$ CuI _2 \rightarrow $\square$ CaI _2+ $\square$ Cu ( OH )_2[/tex] Complete the table to determine how many atoms of each element are present in the reactants and products. | Element | Reactant | Products | | :------ | :------- | :------- | | Ca | $\square$ | $\square$ | | O | $\square$ | $\square$ | | H | $\square$ | $\square$ | | Cu | $\square$ | $\square$ | | I | $\square$ | $\square$ |

[Answered] Translate the following statements into chemical equations and then balance them: a. Hydrogen combines with nitrogen to form ammonia. b. Hydrogen sulphide burns in air to give water and sulphur dioxide. c. Zinc reacts with dilute sulphuric acid to give zinc sulphate and hydrogen. d. Potassium metal reacts with water to give potassium hydroxide and hydrogen.

[Answered] {\begin{tabular}{|c|c|} \hline liquid & density \ \hline glycerol & $1.3 g \cdot mL ^{-1}$ \ \hline dimethyl sulfoxide & $1.1 g \cdot mL ^{-1}$ \ \hline acetone & $0.79 g \cdot mL ^{-1}$ \ \hline methyl acetate & $0.93 g \cdot mL ^{-1}$ \ \hline ethanolamine & $1.0 g \cdot mL ^{-1}$ \ \hline \end{tabular}} Next, the chemist measures the volume of the unknown liquid as $1574 . cm ^3$ and the mass of the unknown liquid as {\begin{tabular}{|l|l|} \hline Calculate the density of the liquid. Round your answer to 3 significant digits. & $\square$ $g \cdot mL ^{-1}$ \ \hline Given the data above, is it possible to identify the liquid? & yes no \ \hline If it is possible to identify the liquid, do so. & glycerol dimethyl sulfoxide acetone methyl acetate ethanolamine \ \hline \end{tabular}}

[Answered] A physical chemist measures the temperature [tex]$T$[/tex] inside a vacuum chamber. Here is the result: [tex]$T=-19 .{ }^{\circ} C$[/tex] Convert [tex]$T$[/tex] to SI units. Round your answer to 3 significant figures.

[Answered] An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?