3. (05.05 LC) Consider the reaction 2CuCl2 + 4KI -- 2Cul + 4KCI + I2. If 4 moles of CuCl2 react with 4 moles of KI, what is the limiting reactant? (3 points) A. CuCl2 B. KI C. CuI D. I2

B. KI

Explanation:

Limiting reactant in a reaction is defined as the reactant that is totally consumed when the reaction is occuring.

For the reaction:

2CuCl₂ + 4KI → 2CuI + 4KCl + I₂

2 moles of CuCl₂ react with 4 moles of KI

If 4 moles of CuCl₂ react, the moles of KI required are:

4 moles CuCl₂ * (4 moles KI / 2 moles CuCl₂) = 8 moles KI are required

As there are just 4 moles of KI, Ki is limiting reactant and right answer is:

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.