Its the second one. Add the exponents and you'll get 7
The answer is O2.
The ionic charge of something can be determined by it's place in the periodic table.
Ionic Lewis Dot Structure for BaF2, hope this helps.
Because the formation of rust is a kind of chemistry reaction.
After chemistry reaction, compound with new properties is produced.
Of course, color is one of the new properties.
For example, if you put iron in colorless acid solution, a green solution is made.
This kind of chemisty reaction differs from physical reaction, for example, pigment with one color dissolves in liquid, a liquid with same color is made.
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:
brainly.com/question/26694427
