Answer:its the thrid one i think
Explanation:
Answer:
In physics, action is an attribute of the dynamics of a physical system from which the equations of motion of the system can be derived through the principle of stationary action. ... Action has dimensions of energy⋅time or momentum⋅length, and its SI unit is joule-second.
Explanation:
hope it helps
Based on the chemical equation, to balance the equation we use 2 as a coefficients of HCl on left hand side of reaction.
<h3>What is balanced equation?</h3>
Balanced chemical equations are those equation in which each entities are present in same amount on left side as well as on the right side of the chemical reaction.
Given chemical reaction is:
Zn + HCl → ZnCl₂ + H₂
Above reaction is not balanced equation as number of chlorine and hydrogen atoms are not same, so balanced equation will be:
Zn + 2HCl → ZnCl₂ + H₂
Hence we add 2 as a coefficient of HCl to balance the equation.
To know more about balance equation, visit the below link:
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