Final answer:
Only two of the listed molecules, H2Te (hydrogen telluride) and CO (carbon monoxide), are expected to be isolable compounds due to their chemical plausibility and known stability.
Step-by-step explanation:
The question asks how many of the following molecules are expected to be isolable compounds: OF4, H2Te, F3NaBr, NaBr2, CO.
To determine this, we'll need to consider the chemical plausibility of each molecule:
- OF4 - Oxygen tetrafluoride is not a stable molecule because oxygen typically forms two bonds, not four.
- H2Te - Hydrogen telluride is a valid and isolable compound.
- F3NaBr - This molecule is not chemically plausible as it suggests sodium bonding with both fluorine and bromine in an unstable manner.
- NaBr2 - Sodium dibromide is not a recognized chemical compound; sodium typically forms NaBr (sodium bromide), a stable ionic compound.
- CO - Carbon monoxide is a well-known and isolable compound.
Based on chemical plausibility and known compound stability, we can conclude that only two of the molecules listed are expected to be isolable compounds: H2Te (hydrogen telluride) and CO (carbon monoxide).
Therefore, the correct answer is option b. two.