1.Easy
What is gamma radiation?
- AA fast stream of protons from the nucleus
- BHigh-energy electromagnetic radiation with no mass or charge
- CA slow-moving electron
- DA stream of helium nuclei with a positive charge
2.Easy
What is activation energy?
- AThe energy needed to melt a solid
- BThe minimum energy reacting particles need for a reaction to happen
- CThe total energy released once the reaction has finished
- DThe energy stored in the products
3.Easy
In which state are most metals at room temperature?
- ASolid
- BLiquid
- CGas
- DPlasma
4.Medium
What kind of bond is found in a molecule of oxygen gas, O₂?
- AA polar covalent single bond
- BAn ionic bond
- CA metallic bond
- DA nonpolar covalent double bond
5.Medium
What is the name of the compound CaCO₃?
- ACalcium carbonate
- BCalcium carbide
- CCalcium oxide
- DCarbon calcium trioxide
6.Medium
Water can act as an acid in some reactions and as a base in others. What is such a substance called?
- ASaturated
- BIsotonic
- CNeutral
- DAmphoteric
7.Hard
Which isotope notation describes an atom with 8 protons and 10 neutrons?
- ANeon-18
- BOxygen-10
- COxygen-18
- DArgon-18
8.Hard
Raising the temperature by 10 °C can roughly double the rate of many reactions. What is the main reason?
- AThe activation energy itself is lowered by the extra heat
- BThe particles become larger and easier to hit
- CMany more collisions have at least the activation energy
- DThe reaction becomes more exothermic
Answer key
- 1. B · High-energy electromagnetic radiation with no mass or charge
- 2. B · The minimum energy reacting particles need for a reaction to happen
- 3. A · Solid
- 4. D · A nonpolar covalent double bond
- 5. A · Calcium carbonate
- 6. D · Amphoteric
- 7. C · Oxygen-18
- 8. C · Many more collisions have at least the activation energy
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