IdeasCuriosas - Every Question Deserves an Answer Logo

Questions in chemistry

[Answered] Compare the total mass of the reactants to the total mass of the products. What choice demonstrates the Law of Conservation of Mass? [tex]$248 g AgO \rightarrow 216 g Ag +32 g O _2$[/tex] [tex]$95 g CaCO _3 \rightarrow 56 g CaO +44 g CO _2$[/tex] [tex]$30 g Li _2 O +44 g CO _2 \rightarrow 78 g Li _2 CO _3$[/tex] [tex]$81 g HNO _3 \rightarrow 46 g NO _2+32 g O _2+18 g H _2 O$[/tex]

[Answered] Using the thermodynamic information in the ALEKS Data tab, calculate the standard reaction free energy of the following chemical reaction: [tex]$TiCl_4(g)+2 H_2 O(g) \rightarrow TiO_2(s)+4 HCl(g)$[/tex] Round your answer to zero decimal places.

[Answered] Complete the table below by writing the symbols for the cation and anion that make up each ionic compound. The first row has been completed for you. | ionic compound | cation | anion | |---|---|---| | NaCl | $Na ^{+}$ | $Cl ^{-}$ | | $MnI _3$ | | | | $MnBr _2$ | | | | $Ag _2 S$ | | | | $CuCl _2$ | | |

[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] Which statement correctly describes a chemical reaction? A. Reactants come out of a reaction. B. Energy is always released. C. Bonds between atoms break and reform. D. Products go into a reaction.

[Answered] Select the correct answer. What is a substance? A. a uniform mixture that can't be separated B. a mixture that can be separated C. a single component that can't be separated D. a single component that can be separated

[Answered] Calculate the number of moles of [tex]CuCl_2 \[.\] 2H_2O[/tex] in a mass of 2.42 g to 3 significant figures.

[Answered] Balance the entire chemical reaction using an atom inventory. Remember to balance each element in the reaction. [tex]H_2 O_2 \rightarrow O_2+H_2 O[/tex] What is the coefficient for the water, [tex]H _2 O[/tex], in the balanced equation?

[Answered] What's the percent composition of sulfur in [tex]$H _2 SO _4$[/tex]? A) [tex]$2.1 \%$[/tex] B) [tex]$32.7 \%$[/tex] C) [tex]$65.2 \%$[/tex] D) [tex]$98.1 \%$[/tex]

[Answered] Two nitro [tex]$\left( NO _2\right)$[/tex] groups are chemically bonded to a patch of surface. They can't move to another location on the surface, but they can rotate (see sketch at right). It turns out that the amount of rotational kinetic energy each [tex]$NO _2$[/tex] group can have is required to be a multiple of [tex]$\varepsilon$[/tex], where [tex]$\varepsilon=1.0 \times 10^{-24} J$[/tex]. In other words, each [tex]$NO _2$[/tex] group could have [tex]$\varepsilon$[/tex] of rotational kinetic energy, or [tex]$2 \varepsilon$[/tex], or [tex]$3 \varepsilon$[/tex], and so forth - but it cannot have just any old amount of rotational kinetic energy. Suppose the total rotational kinetic energy in this system is initially known to be [tex]$12 \varepsilon$[/tex]. Then, some heat is added to the system, and the total rotational kinetic energy rises to [tex]$87 \varepsilon$[/tex]. Calculate the change in entropy. Two rotating [tex]$NO _2$[/tex] bonded to a surfac Round your answer to 3 significant digits, and be sure it has the correct unit symbol.