1.简单
What are the usual units of molar mass?
- Amol/L
- Bg/mol
- Cg/L
- Dmol/g
2.简单
Where do the mole ratios used in stoichiometry come from?
- AThe coefficients of the balanced equation
- BThe molar masses of the reactants
- CThe subscripts in each formula
- DThe physical states of the substances
3.简单
What does the rate of a reaction measure?
- AHow much product forms in total by the end
- BHow much energy the final products contain
- CHow quickly reactants are used up or products are formed
- DHow hot the reaction gets
4.中等
Which bond joins amino acids together in a protein?
- AA hydrogen bond
- BAn ionic bond
- CA glycosidic bond
- DA peptide bond
5.中等
What is carbon-14 dating used for?
- AMeasuring body temperature
- BEstimating the age of material that was once alive
- CFinding the exact age of rocks that are billions of years old
- DDetecting carbon monoxide in a room
6.中等
Using significant figures, what is 2.5 cm × 3.42 cm?
- A9 cm²
- B8.6 cm²
- C8.550 cm²
- D8.55 cm²
7.困难
一个葡萄糖分子 C₆H₁₂O₆ 中有多少个原子?
- A24
- B72
- C18
- D3
8.困难
Which of these is a redox reaction?
- ACaCO₃ → CaO + CO₂
- BZn + CuSO₄ → ZnSO₄ + Cu
- CAgNO₃ + NaCl → AgCl + NaNO₃
- DNaOH + HCl → NaCl + H₂O
答案
- 1. B · g/mol
- 2. A · The coefficients of the balanced equation
- 3. C · How quickly reactants are used up or products are formed
- 4. D · A peptide bond
- 5. B · Estimating the age of material that was once alive
- 6. B · 8.6 cm²
- 7. A · 24
- 8. B · Zn + CuSO₄ → ZnSO₄ + Cu
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