Question

In an air-conditioned room at 19.0 degree celsius , a spherical balloon had the diameter of 50.0cm . When taken outside on a hot summer day, the balloon expanded to 51.0cm in diameter. What was the temperature outside in degree celsius? Assume that the balloon is a perfect sphere and that the pressure and number of moles of air molecules remains the same.

Answer 1

The volume of a sphere is (4/3)*pi*r^3.
Knowing diameter calculate original volume. Use PV = nRT to calculate n. You don't have P but the problem states P is constant so just use a convenient number like 1 atm.
Then calculate new volume for expanded balloon, plug in everything but T and solve for new T.

Answer 2

Please don't cheat and use this website do your work and learn!