Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Precipitation is a type of displacement reaction in which one the products is formed in the solid state.
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Explanation:
hydrogen + oxygen---> water
“If a glass of full water is placed by a window and 3 hours go by, then the water in the cup will be lower because the water will evaporate.”
Answer:
Image result for The arrangement of the elements from left to right in the period 4 on the periodic table is based on
The periodic table of elements arranges all of the known chemical elements in an informative array. Elements are arranged from left to right and top to bottom in order of increasing atomic number. Order generally coincides with increasing atomic mass. The rows are called periods
Explanation:
Answer:
Because all the planets orbit the sun in the same direction, along a circular flattened disk.
Explanation:
You're welcome bro, sorry for the late answer