Answer:
The first row of elements fits in period <u>6</u>, after the element <u>lanthanum (La)</u>. The second row of elements fits in period <u>7</u>, after the element <u>actinium (Ac). </u>
I hope this helps!
<u>Answer:</u> The balanced chemical equation is 
<u>Explanation:</u>
A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.
For the given unbalanced chemical equation:

<u>On the reactant side:</u>
Atoms of K = 1
Atoms of Cl = 1
Atoms of O = 3
<u>On the product side:</u>
Atoms of K = 1
Atoms of Cl = 1
Atoms of O = 2
To balance the equation, we must balance the atoms by adding 2 infront of both
and
. Also, a coefficient of 3 must be written infront of 
For the balanced chemical equation:

Answer: energy is transferred, but it can go to the products or the reactants.
Explanation: in a chemical reaction, the atoms and molecules that interact with each other are called reactants.