Which of the following leads to a higher rate of effusion?

a. cooler gas sample
b. lower molar mass
c. slower particle movement
d. reduced temperature

b. Lower molar mass.

Explanation:

Thomas Graham found that, at a constant  temperature and pressure the rates of effusion  of various gases are inversely proportional to  the square root of their masses.

∨ ∝ 1/√M.

where, ∨ is the rate of diffusion of the gas.

M is the molar mass of the gas.

As the gas has a lower molar mass, it will have a higher rate of effusion.

Answerd. may include all of these are many definitions of bases: the  brønsted-lowry definition of acids and bases says that bases are proton acceptors.the arrhenius definition of acids and bases says that bases increase [oh⁻] in solution (thereby producing oh⁻ ions)the lewis definition of acids and bases says that bases donate electron pairs.therefore, the sensible answer is that a base may include all of the described characteristics.