1.ง่าย
Which type of radiation is the most penetrating?
- AGamma rays
- BAlpha particles
- CBeta particles
- DThey are all equally penetrating
2.ง่าย
Which property is typical of bases?
- AThey have a pH below 7
- BThey taste sour
- CThey feel slippery
- DThey turn blue litmus red
3.ง่าย
What is a dilute solution?
- AOne in which the solute has reacted with the solvent
- BOne with a small amount of solute in a lot of solvent
- COne with no solvent at all
- DOne with a large amount of solute in a little solvent
4.ปานกลาง
An exothermic reaction is at equilibrium. What happens if the temperature is raised?
- AThe equilibrium shifts toward the reactants
- BThe equilibrium does not change
- CThe reaction becomes endothermic
- DThe equilibrium shifts toward the products, raising the yield
5.ปานกลาง
อุณหภูมิที่สูงขึ้นมักส่งผลต่อปริมาณของแข็งที่ละลายในน้ำอย่างไร
- Aไม่มีผลต่อของแข็ง
- Bของแข็งกลายเป็นแก๊ส
- Cของแข็งละลายได้มากขึ้น
- Dของแข็งละลายได้น้อยลง
6.ปานกลาง
What is the oxidation number of sulfur in H₂SO₄?
- A+4
- B+6
- C−2
- D+2
7.ยาก
Cotton soaked in ammonia (NH₃) and cotton soaked in hydrogen chloride (HCl) are placed at opposite ends of a glass tube. A white ring of ammonium chloride forms closer to the HCl end. What does this show?
- ABoth gases diffuse at the same speed
- BThe lighter NH₃ molecules diffuse faster than HCl molecules
- CThe white ring forms where the gases are heaviest
- DThe HCl molecules diffuse faster than NH₃ molecules
8.ยาก
Ethanol (CH₃CH₂OH) and dimethyl ether (CH₃OCH₃) have the same formula, C₂H₆O, but ethanol boils at a much higher temperature. Why?
- AEthanol has an O–H group, so its molecules form hydrogen bonds with each other
- BDimethyl ether is ionic and ethanol is covalent
- CEthanol has more carbon atoms
- DEthanol molecules are heavier than dimethyl ether molecules
เฉลย
- 1. A · Gamma rays
- 2. C · They feel slippery
- 3. B · One with a small amount of solute in a lot of solvent
- 4. A · The equilibrium shifts toward the reactants
- 5. C · ของแข็งละลายได้มากขึ้น
- 6. B · +6
- 7. B · The lighter NH₃ molecules diffuse faster than HCl molecules
- 8. A · Ethanol has an O–H group, so its molecules form hydrogen bonds with each other
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