The most probable speed of an oxygen molecule in the gas phase at room temperature is 450 m/s. The root-mean-square speed (urms) is therefore equal to 450 m/s. much greater than 450 m/s. slightly less than 450 m/s. much less than 450 m/s. slightly greater than 450 m/s.

Explanation:

We have,

The most probable speed of an oxygen molecule in the gas phase at room temperature is 450 m/s.

The formula of the most probable speed of a gas molecule is given by :

So,

The RMS speed of the gas molecule is given by :

Use equation (1) in above equation :

It is clear that the RMS speed of the gas molecule is greater than 450 m/s.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g