GuideFoot - Learn Together, Grow Smarter. Logo

Questions in chemistry

📝 Answered - Write the empirical formula of at least four binary ionic compounds that could be formed from the following ions: [tex]$Zn^{2+}, Al^{3+}, F^{-}, O^{2-}$[/tex]

📝 Answered - Calculate the change in internal energy (\Delta E) of a system that performs 158 kJ of work on its surroundings and loses 157 kJ of heat. Report your answer with the correct number of significant figures. Do not include units in your answer. Note that internal energy is given the symbol U in some textbooks.

📝 Answered - What would most likely be included in the "Analysis" section of a lab report? A. a discussion of any errors in the experimental data B. a list of the supplies that were used in conducting the experiment C. suggestions for new experiments based on the results D. a description of what the dependent and independent variables were

📝 Answered - The polyatomic ion in this compound is nitrate, [tex]$NO _3$[/tex]. What is the name of the compound? [tex]$Zn (NO _3)_2$[/tex] A. zinc (II) nitrate B. zinc nitrate C. zinc nitrite D. zinc peroxynitrate

📝 Answered - Verify your calculations for the rate. Are you reporting your data with the correct number of significant figures? | Concentration of iodide anion solution (mM) | 20.1 | 20.1 | | :------------------------------------------ | :---- | :---- | | Concentration of thiosulfate anion solution (mM) | 176.0 | 176.0 | | Concentration of hydrogen peroxide solution (mM) | 20.0 | | | Temperature of iodide anion solution (${ }^{\circ} C$ ) | 10.0 | | | Volume used of iodide anion solution ($I ^{-}$)(mL) | 1.0 | | | Volume used of hydrogen peroxide solution ($H _2 O _2$ )( $m _{1+1} y _{11}$ and $y _1$. | 8.8 | | | Time (s) | | | | Observations | | | | Initial concentration of iodide anion in the reaction (mM) | 47.6 | | | Initial concentration of thiosulfate anion in the reaction (mM) | 0.96 | |

📝 Answered - Fill in the systematic names of the following chemical compounds. Note: for compounds containing hydrogen, you may give the common name instead. | molecular formula | name of compound | | :---------------- | :--------------- | | $N _2 F_4$ | | | $NF _3$ | | | $P _4 S_3$ | | | $P _4 S_7$ | | | $H _2 O$ | |

📝 Answered - Consider the reactivity data for 4 unknown elements and their ions. | | I (ion) | J (ion) | K (ion) | L (ion) | | :--------- | :------------ | :------------ | :------------ | :------------ | | Element I | x | Color change | Color change | Color change | | Element J | Color change | x | x | x | | Element K | Color change | x | x | Color change | | Element L | x | x | x | x | What is the relative reactivity of the elements from least to most reactive? A. Element I < Element K < Element J < Element L B. Element I and L are the same. Element J and K are the same. J and K are less than I and L. C. Element L < Element J < Element K < Element I

📝 Answered - Part A $NH _2 OH ( g ) \rightarrow NH _3(g)+ N _2(g)+ H _2 O ( g )$ Express your answer as a chemical equation. Identify all of the phases in your answer.

📝 Answered - Which statement best describes the relationship between activation energy and rate of reaction? A. Increasing the activation energy can increase the rate of a reaction. B. Reducing the activation energy can increase the rate of a reaction. C. Increasing the reaction energy does not alter the rate of reaction. D. Reducing the activation energy can decrease the rate of a reaction.

📝 Answered - Calculate the current that must be passed into a solution of aluminum salt for 1 hr 30 minutes in order to deposit 1.5 g of Aluminum. $(Al = 27)$