Government jobs · Everyday science · 22 questions
Name: ____________________ Date: ____________
The chemical formula of common salt is:
The gas that makes up most of the Earth's atmosphere is:
Vinegar contains:
Baking soda is chemically:
Diamond and graphite are both forms of:
The pH of a neutral solution at 25 °C is:
Rusting of iron needs:
The most abundant gas in the Sun is:
The gas used by plants in photosynthesis is:
Which of the following is a good conductor of electricity?
The chemical symbol of gold is:
The gas used in fire extinguishers is mainly:
Water is a compound of:
The hardest natural substance is:
Which gas is released when zinc reacts with dilute sulfuric acid?
The main ingredient of LPG is:
The ripening of fruits is hastened by the gas:
Which metal is liquid at room temperature?
The pH of lemon juice is about:
Soap is made by the reaction of fats with:
The compound used to treat acidity in the stomach is:
Chlorine is used in water mainly to:
1. C, 2. C, 3. C, 4. D, 5. A, 6. A, 7. B, 8. B, 9. B, 10. B, 11. A, 12. C, 13. C, 14. B, 15. B, 16. D, 17. B, 18. B, 19. D, 20. A, 21. C, 22. D
Common salt is sodium chloride.
Nitrogen is about 78 percent of dry air. Oxygen is about 21 percent.
Household vinegar is a dilute solution of acetic acid.
Baking soda is NaHCO₃, sodium hydrogen carbonate.
They are allotropes of carbon with different structures.
A pH of 7 is neutral, below 7 is acidic and above 7 is basic.
Iron rusts when it is in contact with both oxygen and moisture.
The Sun is mainly hydrogen, with helium as the second most common.
Plants take in carbon dioxide and water, and release oxygen.
Metals such as copper have free electrons, so they conduct well.
Au comes from the Latin aurum.
Carbon dioxide displaces oxygen and cools the fire.
Its formula is H₂O.
Diamond is the hardest known natural material.
Zn + H₂SO₄ gives ZnSO₄ and hydrogen gas.
Liquefied petroleum gas is mostly propane and butane.
Ethylene is a plant hormone that promotes ripening.
Mercury melts at −39 °C.
Lemon juice is acidic because of citric acid.
This reaction is called saponification.
A base such as magnesium hydroxide neutralises excess stomach acid.
Chlorine disinfects drinking water.