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Questions in chemistry

[Done] In addition, which statement below best explains why physical and chemical changes do NOT violate the Law of Conservation of Matter? a. Physical and chemical changes always involve the same reactants and products b. Physical and chemical changes always produce less product than reactant c. Physical and chemical changes do not gain or lose atoms in the formation of the product

[Done] What is the correct formula that would result from the combination of the two ionic species? [tex]$NH _4^{+}$[/tex] and [tex]$SO _4{ }^{2-}$[/tex] A. [tex]$NH _4(SO _4)_2$[/tex] B. [tex]$(NH _4)_2 SO _4$[/tex] C. [tex]$NH _4 SO _4$[/tex] D. [tex]$SO _4(NH _4)_2$[/tex]

[Done] What concentration of $C$ equals 1 in 10,000 solution of Potassium Permanganate?

[Done] 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]$\square$ Na _3 N+$ $\square$ SrF _2 \rightarrow$ $\square$ NaF +$ $\square$ Sr _3 N_2[/tex] Complete the table to determine how many atoms of each element are present in the reactants and products. | Element | Reactant | Products | | :------ | :------- | :------- | | Na | [tex]$\square$[/tex] | [tex]$\square$[/tex] | | N | [tex]$\square$[/tex] | [tex]$\square$[/tex] | | Sr | [tex]$\square$[/tex] | [tex]$\square$[/tex] | | F | [tex]$\square$[/tex] | [tex]$\square$[/tex] |

[Done] Compare the total mass of the reactants to the total mass of the products. What choice demonstrates the Law of Conservation of Mass? [tex]$12 g C + 22 g O_2 \rightarrow 44 g CO_2$[/tex] [tex]$4 g H_2 + 61 g Cl_2 \rightarrow 75 g HCl$[/tex] [tex]$23 g Na + 12 g H_2O \rightarrow 40 g NaOH + 1 g H_2$[/tex] [tex]$10 g H_2 + 46 g N_2 \rightarrow 56 g NH_3$[/tex]

[Done] What is the correct formula that would result from the combination of the two ionic species? [tex]$Mg ^{2+}$[/tex] and [tex]$PO _4{ }^{3-}$[/tex] A. [tex]$Mg _3(PO _4)_2$[/tex] B. [tex]$Mg (PO _4)_3$[/tex] C. [tex]$MgPO _4$[/tex] D. [tex]$Mg _2(PO _4)_3$[/tex]

[Done] 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]$\square$ $Na _3 N+$ $\square$ $SrF _2 \rightarrow$ $\square$ $NaF +$ $\square$ $Sr _3 N_2$[/tex] Complete the table to determine how many atoms of each element are present in the reactants and products. | Element | Reactant | Products | | :------ | :------- | :------- | | Na | $\square$ | | | N | $\square$ | $\square$ | | Sr | $\square$ | $\square$ | | F | $\square$ | $\square$ |

[Done] Consider the chemical equations shown here. [tex]$\begin{array}{l} CH_4(g)+2 O_2(g) \rightarrow CO_2(g)+2 H_2 O(g) \Delta H_1=-802 kJ \\ 2 H_2 O(g) \rightarrow 2 H_2 O(l) \Delta H_2=-88 kJ \end{array}$[/tex] Which equation shows how to calculate [tex]$\Delta H_{ rxn }$[/tex] for the equation below? [tex]$CH_4(g)+2 O_2(g) \rightarrow CO_2(g)+2 H_2 O(l)$[/tex]

[Done] Given the following reaction, what will cause no impact on the equilibrium if the forward reaction is endothermic? [tex]2 PbS(s)+3 O_2(g)+C(s) \rightleftharpoons 2 Pb(s)+CO_2(g)+2 SO_2(g)[/tex] A. decreasing pressure B. adding [tex]SO _2[/tex] C. adding [tex]O _2[/tex] D. putting the reaction in an ice bath

[Done] What is the formula of silver sulfate? A. [tex]$AgSO _4$[/tex] B. [tex]$SO _4 Ag _2$[/tex] C. [tex]$Ag _2 SO _4$[/tex] D. [tex]$Ag _2 SO _3$[/tex]