200- Element ${}^{11}_{6}\text{C}$ by positron emission transforms into which nuclide?
(1) ${}^{11}_{5}\text{B}$ (2) ${}^{10}_{5}\text{B}$ (3) ${}^{12}_{6}\text{C}$ (4) ${}^{11}_{7}\text{N}$
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Calculation Space
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201- A scientist named .............. by calculating the positive charge of atomic nuclei and dividing them by the electrical charge .............. obtained the correct numbers and called them .............. of the elements.

1. [(1)] Moseley -- atomic number
2. [(2)] Rutherford -- proton -- atomic number
3. [(3)] Rutherford -- proton -- relative atomic mass
4. [(4)] Moseley -- electron -- relative nuclear mass

202- An electron with quantum numbers $n = 4,\ l = 3,\ m_l = -2,\ m_s = -\dfrac{1}{2}$, exists in which element's atom?

1. [(1)] Period 5 halogen
2. [(2)] Period 4 transition metal
3. [(3)] Period 6 noble gas
4. [(4)] First element of lanthanides

203- In which atom do two half-filled orbitals exist?

1. [(1)] $_{32}\text{Ni},\ _{78}\text{Se}$
2. [(2)] $_{32}\text{Ge},\ _{26}\text{Fe}$
3. [(3)] $_{37}\text{Rb},\ _{14}\text{Si}$
4. [(4)] $_{36}\text{Kr},\ _{20}\text{Ca}$

204- Which statement about $\text{Be}_4$ is not correct?

1. [(1)] It is a very reactive metal and reacts with water at room temperature.
2. [(2)] The first ionization energy of its atom is greater than the first ionization energy of atom B.
3. [(3)] The azimuthal quantum number ($l$) and magnetic quantum number ($m_l$) of its electrons are all zero.
4. [(4)] Its atomic radius, compared to carbon, is larger and its electronegativity is less than carbon.

205- If the number of electrons in sublayer $4s$ of atom A is twice the number of electrons in the sublayer below $3d$ of atom B, and the number of electrons in this sublayer in atom A is half the number of electrons in this sublayer in atom B, which two elements are in period four of the periodic table, from right to left respectively?

1. [(1)] $_{29}\text{Cu},\ _{24}\text{Cr}$
2. [(2)] $_{29}\text{Cu},\ _{25}\text{Mn}$
3. [(3)] $_{30}\text{Zn},\ _{24}\text{Cr}$
4. [(4)] $_{30}\text{Zn},\ _{25}\text{Mn}$

206- In which reaction, the energy released is called the lattice energy of magnesium chloride?

1. [(1)] $\text{Mg}^{2+}(\text{s}) + 2\text{Cl}^-(\text{g}) \rightarrow \text{MgCl}_2(\text{s})$
2. [(2)] $\text{Mg}(\text{s}) + \text{Cl}_2(\text{g}) \rightarrow \text{MgCl}_2(\text{s})$
3. [(3)] $\text{Mg}^{2+}(\text{g}) + 2\text{Cl}^-(\text{g}) \rightarrow \text{MgCl}_2(\text{g})$
4. [(4)] $\text{Mg}^{2+}(\text{g}) + 2\text{Cl}^-(\text{g}) \rightarrow \text{MgCl}_2(\text{s})$

207- Which statement about ozone is correct?

1. [(1)] Its molecule has a linear structure and is nonpolar.
2. [(2)] The length of the two oxygen--oxygen bonds in the ozone molecule are equal.
3. [(3)] Its molecule has a bent structure and is more stable than the oxygen molecule.
4. [(4)] It is an allotrope of oxygen and each oxygen atom in it has two lone pairs of electrons.

208- Regarding the molecules $\text{H}_2\text{S}$, $\text{PCl}_3$, and $\text{SiCl}_4$, from right to left:

1. [(1)] Their central atoms have 2, 1, and 1 nonbonding electron pairs respectively.
2. [(2)] Their central atoms have 2, 3, and 4 electronic shells respectively.
3. [(3)] They have a bent shape, trigonal pyramidal, and tetrahedral respectively.
4. [(4)] Polar, nonpolar, and polar respectively.

209- The ball-and-stick model ............ molecule shows ............ and the presence of ............ hydroxyl groups in this molecule is confirmed.
[Figure: Ball-and-stick molecular model showing a chain of carbon atoms with OH groups]

1. [(1)] ball and stick -- glucose -- five
2. [(2)] ball and stick -- glycerol -- three
3. [(3)] structural expanded -- glucose -- five
4. [(4)] structural expanded -- glycerol -- three

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210 -- Which chemical formula is related to an ester and its name is correct?
(1) $\text{H}-\overset{\displaystyle O}{\overset{\displaystyle \|}{C}}-\text{O}-\text{CH}_3$ , methyl acetate (2) $\text{C}_7\text{H}_5-\text{ONa}$ , sodium octanoate
(3) $\text{CH}_3-\overset{\displaystyle O}{\overset{\displaystyle \|}{C}}-\text{ONa}$ , sodium acetate (4) $\text{CH}_3-\overset{\displaystyle O}{\overset{\displaystyle \|}{C}}-\text{O}-\text{CH}_2-\text{CH}_3$ , ethyl octanoate

211 -- Which statement about phenol is not correct?
(1) It is a toxic compound and is used in the production of aspirin and disinfectants.
(2) It has a hydroxyl functional group and can form hydrogen bonds.
(3) Like benzene, its empirical formula is the same as benzene, but its experimental properties are different.
(4) Its molecules, in the presence of a catalyst and heat, are converted to cyclohexane by hydrogen.

212 -- $0.6$ mol of which metal ion reacts with fluoride ion to form $46.8$ grams?
$$(\text{Ga} = 70\ ,\ \text{Ca} = 40\ ,\ \text{Al} = 27\ ,\ \text{Mg} = 24\ \text{ and }\ \text{F} = 19 : \text{g.mol}^{-1})$$
(1) Al (2) Mg (3) Ca (4) Ga

213 -- If the percent yield of the following reaction (after balancing) is $80\%$, and $9.2$ grams of ethanol is used in the reaction, how many grams of diethyl ether are obtained?
$$(H = 1\ ,\ C = 12\ ,\ O = 16 : \text{g.mol}^{-1})$$
$$\text{CH}_3\text{CH}_2\text{OH} \xrightarrow[\text{heat}]{\text{catalyst}} \text{CH}_3\text{CH}_2\text{OCH}_2\text{CH}_3 + \text{H}_2\text{O}$$
(1) $5.92$ (2) $7.4$ (3) $11.84$ (4) $23.68$

214 -- The number of atoms participating in the balanced equation of ethane combustion compared to the balanced equation of aluminum reaction with hydrochloric acid \ldots\ldots\ldots and in the reaction, \ldots\ldots\ldots gaseous product is produced.
(1) less -- one of the two -- becomes.
(2) more -- both -- become.
(3) less -- none of the two -- does not become.
(4) more -- one of the two -- becomes.

215 -- If $45\text{ mL}$ of $30\text{ g.L}^{-1}$ magnesium sulfate solution is mixed with $50\text{ mL}$ of $\dfrac{2}{7}\text{ mol.L}^{-1}$ sodium phosphate solution, what is the limiting reagent and how many moles of precipitate are formed?
$$(O = 16,\ Mg = 24\ ,\ S = 32 : \text{g.mol}^{-1})$$
(1) magnesium sulfate $-\ 7.5\times10^{-3}$ (2) sodium phosphate $-\ 5\times10^{-3}$
(3) magnesium sulfate $-\ 3.75\times10^{-3}$ (4) sodium phosphate $-\ 2.5\times10^{-3}$

216 -- In a bomb calorimeter containing $2\text{ kg}$ of water, a mixture of $0.5$ mol of methane gas and $2$ mol of oxygen gas is burned $(\Delta E_{\text{combustion}} = -890\text{ kJ.mol}^{-1})$. The temperature inside the calorimeter increases by approximately how many degrees Celsius? (The heat absorbed by the calorimeter body and gases is neglected, and the specific heat capacity of water is $4.2\text{ J.g}^{-1}.^\circ\text{C}^{-1}$.)
(1) $13$ (2) $26$ (3) $53$ (4) $106$

217 -- Which statement is correct?
(1) $q_p$ equals $\Delta E - w$ and is called enthalpy of reaction.
(2) The specific heat capacity of each substance depends on the amount of the substance.
(3) Based on the second law of thermodynamics, energy does not disappear but changes from one form to another.
(4) In a reaction where $\Delta H < 0$ and $\Delta S > 0$, the reaction is not spontaneous and reaches equilibrium in a closed container.
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218. Given that the standard enthalpy of formation of $\mathrm{HCl(g)}$ is $-184\,\mathrm{kJ.mol^{-1}}$ and $\Delta S^\circ$ of the reaction $$\mathrm{H_2(g) + Cl_2(g) \rightarrow 2HCl(g)}$$ at $27^\circ\mathrm{C}$ is $+40\,\mathrm{J.K^{-1}}$, $\Delta G^\circ$ of this reaction is how many kilojoules?
(1) $+365$ (2) $+369$ (3) $-380$ (4) $-196$

219. If $\Delta H^\circ$ of combustion of ethanol is $-1370\,\mathrm{kJ}$, $\Delta H^\circ$ of formation of it is $-275\,\mathrm{kJ.mol^{-1}}$, and $\Delta H^\circ$ of formation of $\mathrm{H_2O(l)}$ is $-286\,\mathrm{kJ.mol^{-1}}$, then $\Delta H^\circ$ of formation of $\mathrm{CO_2}$ gas is how many kilojoules per mole?
(1) $-118.5$ (2) $-393.5$ (3) $-787$ (4) $-237$

220. The solubility of lead(II) chloride at a certain temperature is $1391\,\mathrm{g}$ per $100\,\mathrm{g}$ of water. The concentration of the solution at this temperature is $1\,\mathrm{g.mL^{-1}}$ (density of water). Which value of $\mathrm{mol.L^{-1}}$ is correct? $$(\mathrm{Pb} = 207.2 \quad \mathrm{Cl} = 35.5\,:\,\mathrm{g.mol^{-1}})$$
(1) $\Delta \times 10^{-3}$ (2) $5\times10^{-4}$ (3) $5.7\times10^{-4}$ (4) $5.7\times10^{-4}$

221. With 4 milligrams of sodium hydroxide, approximately how many grams of solution of 50 ppm can be prepared, and this solution contains how many moles of sodium hydrogen sulfate? $$(\mathrm{H=1,\ O=16,\ Na=23\,:\,g.mol^{-1}})$$
(1) $10^{-3}$, $\Delta.5$ (2) $10^{-4}$, $\Delta.5$ (3) $10^{-3}$, $8.0$ (4) $10^{-4}$, $8.0$

222. In the complete reaction of $49.10\,\mathrm{g}$ of a half-molar solution of phosphoric acid with sufficient calcium hydroxide solution, how many moles of substance are formed in water? $$(\mathrm{H=1,\ O=16,\ P=31\,:\,g.mol^{-1}})$$
(1) $2.5\times10^{-2}$ (2) $4.5\times10^{-2}$ (3) $2.5\times10^{-3}$ (4) $4.5\times10^{-3}$

223. The molecular formula of a branched-chain alkyl sulfonate surfactant that has 14 carbon atoms is which of the following?
(1) $\mathrm{C_{14}H_{29}SO_4Na}$ (2) $\mathrm{C_{14}H_{29}SO_4Na}$ (3) $\mathrm{C_{20}H_{33}SO_4Na}$ (4) $\mathrm{C_{20}H_{33}SO_4Na}$

224. Which statement about the transition state is not correct?
(1) The more unstable it is, the faster the forward reaction rate.
(2) It is a very unstable species that forms along the reaction pathway.
(3) Its energy level is higher than the $\Delta H$ of the reaction above the energy of the reactants.
(4) In it, initial bonds are in the process of breaking and new bonds are in the process of forming.