1.やさしい
What does the octet rule state?
- AAtoms tend to gain, lose or share electrons to get 8 outer electrons
- BEvery stable molecule contains exactly 8 atoms
- CAn atom can form a maximum of 8 covalent bonds
- DEvery stable atom has exactly 8 protons in its nucleus
2.やさしい
原子間で電子が共有されるときにできる結合はどれか。
- Aイオン結合
- B核結合
- C金属結合
- D共有結合
3.やさしい
An instant cold pack feels cold when the substance inside dissolves. How is this dissolving process classified?
- AExothermic
- BA combustion reaction
- CEndothermic
- DA neutralisation reaction
4.ふつう
What is the molar mass of calcium carbonate, CaCO₃ (Ca = 40, C = 12, O = 16 g/mol)?
- A116 g/mol
- B100 g/mol
- C68 g/mol
- D84 g/mol
5.ふつう
Which gas forms when hydrochloric acid reacts with calcium carbonate?
- AHydrogen
- BOxygen
- CCarbon dioxide
- DChlorine
6.ふつう
What colour is phenolphthalein indicator in a basic solution?
- AYellow
- BBlue
- CPink
- DColourless
7.むずかしい
Ethanol (CH₃CH₂OH) and dimethyl ether (CH₃OCH₃) have the same formula, C₂H₆O, but ethanol boils at a much higher temperature. Why?
- AEthanol has more carbon atoms
- BEthanol has an O–H group, so its molecules form hydrogen bonds with each other
- CEthanol molecules are heavier than dimethyl ether molecules
- DDimethyl ether is ionic and ethanol is covalent
8.むずかしい
Which element has the electron configuration 1s² 2s² 2p⁶ 3s² 3p⁵?
- AChlorine
- BSulfur
- CArgon
- DFluorine
解答
- 1. A · Atoms tend to gain, lose or share electrons to get 8 outer electrons
- 2. D · 共有結合
- 3. C · Endothermic
- 4. B · 100 g/mol
- 5. C · Carbon dioxide
- 6. C · Pink
- 7. B · Ethanol has an O–H group, so its molecules form hydrogen bonds with each other
- 8. A · Chlorine
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