Question

answer on the next slide
based on the introductory videos and your knowledge of the
periodic table, which of the following elements do we think will
produce the biggest reaction with water and why?
ca
mg
fe
al
zn

Explanation:

Step1: Analyze reactivity trends

In the periodic table, reactivity of metals with water generally increases down a group. Calcium (Ca) is in group 2, while Mg is also in group 2 but above Ca. Al, Fe, Zn are in different groups with lower reactivity compared to group 2 metals in terms of reaction with water.

Step2: Consider reaction with water

Calcium reacts with water as \(Ca + 2H_2O=Ca(OH)_2 + H_2\uparrow\). Its position in the periodic table (lower in group 2 compared to Mg) makes it more reactive. Mg reacts with steam (\(Mg + H_2O(g)=MgO + H_2\uparrow\)) but not as vigorously with liquid water as Ca. Al, Fe, Zn have more stable oxides or lower reactivity with water under normal conditions.

Answer:

Ca. Because in the periodic table, for group 2 metals (where Ca and Mg belong), reactivity with water increases down the group. Ca is below Mg in group 2. Also, compared to Al, Fe, Zn (which are in different groups with generally lower reactivity with water under normal conditions), Ca will have a more vigorous reaction with water.