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Questions in chemistry

[Done] Describe each phase of matter based on their molecular arrangement. S ______ L ______ G ______ Give example materials for each phase of matter. S ______ and ______ L ______ and ______ G ______ and ______

[Done] What is the molecular formula of the compound [tex]CH _2[/tex] with molar mass [tex]=168[/tex] [tex]g / mol[/tex]? A. [tex]C _{10} H _{20}[/tex] B. [tex]C _{12} H _{24}[/tex] C. [tex]C _{11} H _{22}[/tex] D. [tex]C _8 H _{16}[/tex]

[Done] Use atomic diagrams to show how an ionic bond is formed between sodium and chlorine.

[Done] Select the correct answer. This chemical equation is not balanced: [tex]AgBr(s)-Ag(s)+Br_2(g)[/tex] Why isn't it possible for the reaction to occur as indicated by the unbalanced equation? A. There are more substances on the right side of the equation than on the left side. B. There is a gas on the right side of the equation but not on the left side. C. The bromine atoms must go through a liquid state before becoming a gas. D. There is more mass represented on the right side of the equation than on the left side. E. The bromine atoms on the right side of the equation are not bonded to another element.

[Done] Select the correct answer. Copper carbonate [tex]$\left( CuCO _3\right)$[/tex] reacts with hydrochloric acid [tex]$( HCl )$[/tex] according to this equation: [tex]$CuCO _3(s)+2 HCl (a q) \rightarrow CuCl _2(a q)+ H _2 O (f)+ CO _2(g)$[/tex]. Which statement correctly describes the substances in this reaction? A. Exactly one product and two reactants are either liquid or dissolved in water. B. Exactly one of the reactants is in a water-based solution, but none of the products are. C. The reactants include both a liquid and a gas. D. Exactly one reactant is a solid, and exactly one product is a gas. E. The products include a solid, a liquid, and a gas.

[Done] What will be the volume of ammonia gas when [tex]$100 cm^3$[/tex] of nitrogen reacts with [tex]$150 cm^3$[/tex] of hydrogen? Which is the limiting reactant? (All gases are measured at the same temperature and pressure.)

[Done] Study the given table and answer the following questions. | Period | IA | IIA | IIIA | IVA | VA | VIA | VIIA | VIIIA (Zero Group) | |---|---|---|---|---|---|---|---|---| | 2nd | Li | Be | B | C | N | O | F | Ne | | 3rd | Na | Mg | Al | Si | P | S | Cl | Ar | i. Name any one metal with valency 3 and one non-metal with valency 2. ii. Which element is inert in the second period and why? iii. What change will occur in the atomic size of elements while moving from left to right in third period and why?

[Done] Lars is balancing equations with his study group. He is unsure about one equation because each member of the study group has a different answer. Which of the following equations is correctly balanced? [tex]$Ca ( OH )_2+ H _3 PO _4 \rightarrow Ca _3( PO _4)_2+6 H _2 O$[/tex] [tex]$3 Ca ( OH )_2+2 H _3 PO _4- Ca _3( PO _4)_2+6 H _2 O$[/tex] [tex]$3 Ca ( OH )_2+2 H _3 PO _4- Ca _3( PO _4)_2+3 H _2 O$[/tex] [tex]$Ca ( OH )_2+2 H _3 PO _4 \rightarrow Ca _3( PO _4)_2+6 H _2 O$[/tex]

[Done] Predict the products of the following double displacement reactions and balance the equation. a. [tex]Na_2 CO_3(aq)+CuSO 4(aq) \longrightarrow[/tex] b. [tex]\left( NH _4\right)_2 SO _4( aq )+ CaCl _2( aq )[/tex] c. [tex]Na _2 CO _3( aq )+ Cu \left( NO _3\right)_2( aq ) \longrightarrow[/tex] d. [tex]Mg ( OH )_2( aq )+ HNO _3( aq )[/tex]

[Done] $CO_{(1)}+2 H_{2(\,\theta)} \rightarrow CH_3 OH_{(0)}$ Using the following data, what would be the enthalpy change for the reaction? (i) $C _{(s)}+\frac{1}{2} O _{2(s)} \rightarrow CO _{(s)}$ $\Delta H ^0=-110.5 kJ / mol$ (ii) $C _{(\text {a })}+ O _{2(\text { g })} \rightarrow CO _{2(\text { g })}$ $\Delta H ^0=-393.5 kJ / mol$ (iii) $H _{2(g)}+\frac{1}{2} O _{2(s)} \rightarrow H _2 O _{( i )}$, $\Delta H ^0=-285.5 kJ / mol$ (iv) $CH _3 OH _{(1)}+\frac{3}{2} O _{2(\beta)} \rightarrow 2 H _2 O _{(\beta)}+ CO _{2(\beta)}$ $\Delta H ^0=-726.6 kJ / mol$