Boyle's Law for gases is:

a. true for all gases only accurate at room temperature

b. just a model and therefore accurate for no real gas

c. accurate for most gases in most temperature ranges

d. a good example of a "law" that is now found to be incorrect

b. just a model and therefore accurate for no real gases

Explanation:

Boyle's Law was determined and is applied for ideal gases, this is, those gases that:

- Do not have any interaction between their particles (neither attraction nor repulsion)

- Any collision between its particles is perfectly elastic

With these conditions, Boyle found that pressure and volume (in a constant temperature) are inversely proportional, which can be expressed as:

PV = k, where "k" is a constant

So, when pressure increases, volume decreases, and viceversa.

If we have to different conditions (1 and 2) of pressure and volume (at constant temperature), this can be expressed like:

P₁V₁ = P₂V₂ = constant

The current and complete equation that links temperature, pressure, mass (in moles) and volume is:

PV = nRT

Real gases do not strictly comply with this law, as its particles has interactions and collisions are not perfectly elastic. This law is more accurate for gases with low molecular mass, and with low pressure and/or high temperature conditions (under these conditions, interactions can be neglected)

Another term that can gives us an idea whether a gas is ideal or not, is the compressibility coefficient Z:

Z = PV/RT

For ideal gases, Z = 1, as long as the gas moves away from ideality, Z is totally different from 1