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Questions in chemistry

[Done] Q8. The list contains the electronic configuration of some atoms: 2,8,1 2,7 2,5 2,3 2,8,4 2,5 2,8,7 2,8 i. Which of these atoms are in Group 1 of the periodic table? ii. Which of these atoms are in Group 7 of the periodic table? iii. Which of these atoms are in Group 0 of the periodic table? iv. Write the electronic configuration of an atom in Group 4 of the periodic table.

[Done] Consider the following intermediate chemical equations: [tex]$\begin{array}{l} 2 P(s)+3 Cl_2(g) \rightarrow 2 PCl_3(l) \\ PCl_3(l)+Cl_2(g) \rightarrow PCl_5(s) \end{array}$[/tex] When you combine the intermediate chemical equations, which substance do you cancel out? A. P B. [tex]$Cl _2$[/tex] C. [tex]$PCl _3$[/tex] D. [tex]$PCl _5$[/tex]

[Done] Which of the following is the empirical formula for $C _4 H _8$? A. $CH _4$ B. $CH _2$ C. $C _2 H _2$ D. $C _6 H _6$

[Done] Consider the following intermediate chemical equations: [tex]\begin{array}{l} 2 Na(s)+Cl 2(g) \rightarrow 2 NaCl(s) \\ 2 Na_2 O(s) \rightarrow 4 Na(s)+O_2(g) \end{array}[/tex] In the final chemical equation, NaCl and [tex]O _2[/tex] are the products that are formed through the reaction between [tex]Na _2 O[/tex] and [tex]Cl _2[/tex]. Before you can add these intermediate chemical equations, you need to alter them by: A. multiplying the second equation by ? B. multiplying the first equation by 2. C. multiplying the first equation by (1/2). D. multiplying the second equation by (1/4).

[Done] Formaldehyde, ethylbenzene, and hydrogen sulfide are all chemicals that are: A. toxic B. corrosive C. irritant D. harmless

[Done] Consider the following intermediate chemical equations: [tex]\begin{array}{ll} P_4(s)+3 O_2(g) \rightarrow P_4 O_6(s) & \Delta H_1=-1,640 kJ \\ P_4 O_{10}(s) \rightarrow P_4(s)+5 O_2(g) & \Delta H_2=2,940.1 kJ \end{array}[/tex] What is the enthalpy of the overall chemical reaction [tex]P _4 O _6(s)+2 O _2(g) \rightarrow P _4 O _{10}(s)[/tex] ? A. -4,580 kJ B. -1,300 kJ C. 1,300 kJ D. 4,580 kJ

[Done] Which is a characteristic of all matter? A. They are metal B. They have a charge C. They are made of two or more types of atoms. D. They form chemical bonds through electron sharing.

[Done] Use the periodic table to complete each nuclear fusion equation. ${ }_1^2 H +{ }_1^3 H \rightarrow{ }_B^A He$ ${ }_7^{14} N+{ }_1^1 H \rightarrow{ }_D^{ C } E$ A: $\square$ C: $\square$ B: $\square$ D: $\square$ E: $\square$

[Done] What characteristic of CFC refrigerants makes them more likely to reach the stratosphere than most other compounds that contain chlorine? A. CFCs are attracted to the dust in the stratosphere B. CFCs are attracted to the static in the stratosphere C. CFCs that contain chlorine but not hydrogen are so stable that they do not break down in the lower atmosphere D. CFCs are lighter than other damaging compounds making them easier to float upward when released

[Done] The shell having $n=3$ contains how many subshells, how many orbitals, and up to how many electrons? A. 3; 6; 12 B. 2; 4; 8 C. 3; 12; 36 D. 3; 9; 18 E. 3; 6; 18