Answer:
1
only 4 is the significant figure
we take tailing zeroes as significant figures only in case of decimals
Acid base reactions also known as neutralization reactions are reactions that occur between acids and bases thus the name. Anytime this happens the product will niether an acid or base it will be neutralized to a neutral pH as in that of pure water pH 7.
Precipitation reactions occur when cations and anions in aqueous solution combine to form an insoluble ionic solid called a precipitate. Whether or not such a reaction occurs can be determined by using the solubility rules for common ionic solids.
Answer:
Mechanical Energy to Thermal Energy
When you strike a match, it moves through the air until it rubs against a surface. The rubbing produces the heat required to light the match. This is a transformation from mechanical energy to thermal (heat) energy.
Explanation:
It increases because the electrons are held tighter together by the higher effective nuclear charge. The electrons are held in lower energy orbitals and closer to the nucleus and more tightly bound and harder to remove from the atom.
Answer:
C. 
Explanation:
Hello there!
In this case, according to the given chemical reaction, it turns out possible to realize there is one sulfur atom on each side of the chemical equation but two hydrogen atoms on the left and one on the right, which means the latter must be balanced in agreement to the law of conservation of mass.
In such a way, by setting a 2 on H⁺, the reaction will be balanced:

Now, we count the transfer electrons for sulfur from -2 to 0 as 2e⁻ on the right, which will match with the option C.

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