A 3.0-L balloon containing helium gas, He, at 17 °C, was taken outdoors where the temperature was close to 0 °C. What happened to the volume of the balloon?
The gas volume increased.
The gas volume decreased.
The gas volume remains constant.
O With the provided information, gas volume cannot be modeled.

The gas volume remains constant

Explanation:

The volume stayed constant however the balloon may seem to have shriveled or deflated upon walking outside due to the helium condensing in  the cooler climate.

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