Arrange the following in order of increasing atomic radius : Co, Mo, S, Ge, Cs
Atomic radius decreases across the table and increases down the table.
So what do you think the answer should be?
To arrange the given elements in order of increasing atomic radius, you need to consider the trends across the periodic table.
Here's how you can approach it:
1. Identify the elements and their positions on the periodic table:
- Co (Cobalt) is in the transition metals group.
- Mo (Molybdenum) is also a transition metal.
- S (Sulfur) is in the nonmetal group.
- Ge (Germanium) is a metalloid located in group 14.
- Cs (Cesium) is an alkali metal in group 1.
2. Note the general trend of atomic radius:
Going from left to right across a period (horizontal row), atomic radius generally decreases due to increased effective nuclear charge.
Going down a group (vertical column), atomic radius generally increases as additional electron shells are added.
3. Apply the trend to the given elements:
- Comparing Co and Mo: Both elements are transition metals, but Mo is located further to the right on the periodic table, so it has a smaller atomic radius. Thus, the order is Co < Mo.
- Comparing Mo and S: Mo is a transition metal, and S is a nonmetal. Nonmetals have smaller atomic radii than transition metals, so the order is S < Mo.
- Comparing S and Ge: Both elements are in the same period (row), but Sulfur is on the right side as a nonmetal, while Germanium is on the left side as a metalloid. Therefore, Germanium has a larger atomic radius. The order is S < Ge.
- Comparing Ge and Cs: Germanium is a metalloid, and Cesium is an alkali metal. Alkali metals have larger atomic radii compared to metalloids. Thus, the order is Ge < Cs.
Putting it all together, the elements arranged in increasing atomic radius are:
S < Mo < Co < Ge < Cs.