The number of molecules/ions that show linear geometry among the following is ______. SO2, BeCl2, CO2, N3 – , NO2, F2O, XeF2, NO2 + , I3 – , O3

To find out which molecules or ions have linear geometry, we use the VSEPR (Valence Shell Electron Pair Repulsion) theory. This theory says that electron pairs around the central atom repel each other and arrange themselves to be as far apart as possible. The shape depends on the number of bonding pairs and lone pairs around the central atom.

Linear geometry happens when the central atom has two regions of electron density and no lone pairs, or when the lone pairs do not affect the shape (like in some ions). The bond angle in linear molecules is about 180 degrees.

Let's analyze each molecule/ion:

• SO2: Central atom S has 3 regions (2 bonds + 1 lone pair) → bent shape, not linear.
• BeCl2: Central atom Be has 2 bonds, no lone pairs → linear.
• CO2: Central atom C has 2 double bonds, no lone pairs → linear.
• N3– (azide ion): Resonance structure with linear shape.
• NO2: Central atom N has 2 bonds + 1 lone pair → bent, not linear.
• F2O: Central atom O has 2 bonds + 2 lone pairs → bent, not linear.
• XeF2: Central atom Xe has 2 bonds + 3 lone pairs → linear.
• NO2+: Central atom N has 2 bonds, no lone pairs → linear.
• I3–: Central atom I has 2 bonds + 3 lone pairs → linear.
• O3: Central atom O has 2 bonds + 1 lone pair → bent, not linear.

Counting the linear ones: BeCl2, CO2, N3–, XeF2, NO2+, I3– → total 6.

Imagine molecules as tiny shapes made by balls (atoms) connected by sticks (bonds). Some shapes are straight lines, like a straight stick, and some are bent or have angles. This question asks how many molecules or ions from a list look like a straight line. To find out, we use a simple rule called VSEPR theory, which helps us guess the shape based on how many bonds and lone pairs the central atom has. If the shape is straight, we say it has linear geometry.

Step 1: Identify the central atom and count bonding pairs and lone pairs.

Step 2: Use VSEPR theory to predict shape.

Step 3: Check if the shape is linear (2 bonding pairs, 0 lone pairs or lone pairs arranged so shape remains linear).

Analyzing each:

• SO2: Bent (not linear)
• BeCl2: Linear
• CO2: Linear
• N3–: Linear
• NO2: Bent (not linear)
• F2O: Bent (not linear)
• XeF2: Linear
• NO2+: Linear
• I3–: Linear
• O3: Bent (not linear)

Number of linear molecules/ions = 6

Final answer: 6