A person looking to find some of the most common chemical symbols can find these in a few places. The local library may have books on this subject. Some other places that offer information or flash cards of the symbols include Chymist, Quia, ProPofs, and Quizlet.
A cross and a fish
water
oil
The primary agent of chemical weathering is water.
Oxygen as most reactions have it although it could also be hydrogen
The most common cause of chemical weathering is oxygen
The most common cause of chemical weathering is oxygen
It is the symbols shown on traffic signs.
There are no official symbols of Islam. With that being said, some would say the most common symbols that represent Islam are the Star and Crescent. But there are findings in the Quran that specify that either are legitimate official symbols of Islam.
A cross and a fish
The throne and a crown are most common.
You can find a list of common proofreading symbols in style guides such as The Chicago Manual of Style or the Merriam-Webster's Collegiate Dictionary. Online resources, such as the Purdue Online Writing Lab (OWL) or Grammarly, also provide guides on proofreading symbols and their meanings.
Keyboard symbols, such as ! " £ $ % & @ { } are self explanatory. On a laptop (usually) there may be other symbols to be used along with the Ctrl, Alt, and or a special function key (fn) to brighten or dim the screen, to raise or lower the volume, and so on.
water
oil
The primary agent of chemical weathering is water.
Hydrogen.