If this is a true or false question then the answer is true.
It is a scientific hypothesis. A scientific hypothesis must be testable, however there is a significantly more grounded necessity that a testable speculation must meet before it can truly be viewed as logical. This foundation comes essentially from crafted by the rationalist of science Karl Popper, and is called "falsifiability".
Explanation:
Physical changes only change the appearance of a substance, not its chemical composition.
Chemical changes cause a substance to change into an entirely substance with a new chemical formula.
Chemical changes are also known as chemical reactions. The “ingredients” of a reaction are called reactants, and the end results are called products
Answer: 
Explanation:-
Single replacement reaction is a chemical reaction in which more reactive element displaces the less reactive element from its salt solution.
As zinc is more reactive than copper, it could easily displace copper from its aqueous solution and thus leads to formation of zinc (II) sulfate and pure copper.
The chemical reaction can be represented as :
The phases are represented as (s) for solid sate, (l) for liquid state, (g) for gaseous state and (aq) for aqueous state.
Answer:
Explanation:
Strontium chlorate appears as a moist solid or semi-solid slurry of white crystals. May explode under exposure to heat or fire. Used in pyrotechnics
strontium chlorate | Sr(ClO3)2 - PubChem.
Description: Strontium chlorate appears as a ...
Synonyms: STRONTIUM CHLORATE7791-10-...
Molecular Formula: Sr(ClO3)2 or Cl2O6Sr
