Answer:

Explanation:
This reaction type is a single replacement. The format of a single replacement is:

A= Al
B= Ni
C= SO
The coefficient 3 for Ni would become a subscript for AC. After you plug those into the reaction you need to count how many of each are on the left side and try to get the same number on the right side. Both sides must be equal to have a balanced equation.
Answer:
Every oxidation must be accompanied by a reduction.
Explanation:
Oxidation and reduction are complementary processes. There can be no oxidation without reduction and vice versa. It is actually a given an take affair. A specie looses electrons which must be gained by another specie to complete the process. This explains why the selected option is the correct one.
Answer:
A. 2Na + 2H₂O → 2NaOH + H₂
Explanation:
When sodium is reacted with water, a single replacement reaction occurs. The product of the reaction is typically sodium hydroxide and hydrogen gas.
Reactants:
Sodium + water
Product:
Sodium hydroxide + hydrogen gas
So;
2Na + 2H₂O → 2NaOH + H₂
Covalent bonds form when electrons are shared between two nonmetals.
Answer: i would say D or the last one.
Explanation: According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants. The law of conservation of mass is useful for a number of calculations and can be used to solve for unknown masses, such the amount of gas consumed or produced during a reaction.
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