Write a balanced equation to show the reaction between gaseous ethane with gaseous oxygen to form carbon monoxide gas and water vapor. 2C_(2)H_(6)(g)+5O_(2)(g)arrow 4CO(g)+6H_(2)O(g) 2C_(2)H_(6)(g)+7O_(2)(g)arrow 4CO_(2)(g)+6H_(2)O(g) C_(2)H_(6)(g)+5O_(2)(g)arrow 2CO(g)+3H_(2)O(g) C_(2)H_(6)(g)+7O(g)arrow 2CO_(2)(g)+3H_(2)O(g) 2CH_(3)(g)+5O(g)arrow 2CO(g)+3H_(2)O(g)
An aqueous solution contains 0.22 M sodium cyanide. One liter of this solution could be converted into a buffer by the addition of: (Assume that the volume remains constant as each substance is added.) (Select all that apply.) 0.21 mol NaCl 0.21 mol HCN 0.11 mol Ca(OH)_(2) 0.11 mol HNO_(3) 0.22molHNO_(3)
The minimum energy required to initiate a chemical reaction is __ minimum energy initiation energy activation energy starting energy
Which of the following statements is true about endothermic reactions? They release heat to the surroundings The products have less energy than the reactants They absorb heat from the surroundings They occur spontaneously
What is the mass number of a potassium (K) atom that has 20 neutrons? The mass number is __ Blank 1: square
__ is used as a decolorizing agent in the Anthony Method of capsule staining Copper sulfate Water 95% Alcohol 91% Isopropanol
What is the correct formula for calculating molar mass? Molar mass=Massdiv Moles Molar mass=Molesdiv Mass Molar mass=Volume+Density Molar mass=Molestimes Avogadro's number
Which of the following rules is applicable for balancing a chemical equation? Change only the coefficients Add the coefficients and change the subscripts Change only the subscripts Change the coefficients and the subscripts
A gas is cooled from 365 K to 285 K while its volume changes from 12.8 Lto 9.9 L The initial pressure of the gas is 1.9 atm. What is the final pressure of the gas rounded to the nearest tenth? 1.3 atm 2.9 atm 1.9 atm 9.9 atm
What happens to a material if it's dissolved in a solvent? The solute bonds to the solvent, forming new compounds. The solvent is split into its ions. The solute is split into its ions. The solute disappears forever.
Hydrogen sulfide is: A) Odorless B) Colorless C) Not flammable D) Red in color
Question 21 Calculate $\Delta _{r}G^{\circ }$ at $25.0^{\circ }C$ for the reaction below. $2Na(s)+2H_{2}O(l)\rightarrow 2NaOH(aq)+H_{2}(g)$ Given: $\Delta _{r}H^{\circ }=-314kJ$ and $\Delta _{r}S^{\circ }=-117J/K$ (Report your answer in units of kJ, to one decimal place, i.e xxx.x, and no units are necessary in the answer.) (Remember to include a negative sign, if necessary.)
Which type of reaction is represented by the generic equation $AB+CD\rightarrow AD+CB$ combustion decomposition single replacement double replacement
Given the equilibrium constants for the following reactions: $4Cu(s)+O_{2}(g)\rightleftharpoons 2Cu_{2}O(s),K_{1}=6.19$ $4CuO(s)\rightleftharpoons 2Cu_{2}O(s)+O_{2}(g),K_{2}=0.16$ what is K for the system $2Cu(s)+O_{2}(g)\rightleftharpoons 2CuO(s)$ equivalent to? (Report your answer to four decimal places, i.e.xxxx) $\square $
What is the pH of a solution made by combining 0.484 m $NaC_{2}H_{3}O_{2}$ with 0.042 M $HC_{2}H_{3}O_{2}$ ? The $K_{a}$ of acetic acid is $1.75\times 10^{-5}$ (Report your answer to three decimal places, i.e x.xxx)
As pure molecular solids , identify the types of intermolecular forces in each: $PH_{3}$ $\square $ HF $\square $ $CO_{2}$ $\square $
What is the molality of ethanol $(C_{2}H_{5}OH)$ in an aqueous solution that is $48.2\% $ ethanol by mass? (Report your answer to two decimal places, i.e xx.xx, and no units are necessary in the answer.)
What is the molality of ethanol $(C_{2}H_{5}OH)$ in an aqueous solution that is $48.2\% $ ethanol by mass? (Report your answer to two decimal places, ite xxxx, and no units are necessary in the answer.)
Continue to shake until no more salt will come out of the shaker. What happens to the last several crystals of salt that come out? The sodium ions dissolve while the chloride ions sink to the bottom. The salt crystals react with the water to form a new compound. All of the ions separate from each other and dissolve into the water. The salt crystals don't dissolve in the water and fall to the bottom unchanged.
Consider the reaction of magnesium silicide with water shown below: $Mg_{2}Si(s)+4H_{2}O(l)\rightarrow 2Mg(OH)_{2}(aq)+SiH_{4}(g)$ In the reaction of 13.13 g $Mg_{2}Si$ with excess water, 16.03 g $Mg(OH)_{2}$ were produced. Calculate the percent yield of $Mg(OH)_{2}$ Enter the answer rounded to 2 decimal places.Units are not necessary. Answer: $\square $
