The reaction is given by

Barium goes underneath beta decay to form Ceaseum
- Cs is very mellable element
- It can melt on your hand
Opposites attract, like for example magnets, one is positive and the other is negatively charged, they will attract
Gay-Lussac's law gives the relationship between pressure and temperature of a gas.
it states that for a fixed amount of gas of constant volume pressure is directly proportional to temperature.
P/T = k
where P - pressure, T - temperature and k - constant

where parameters for the first instance are on the left side and parameters for the second instance are on the right side of the equation.
temperature should be in the kelvin scale,
T1 = 22 °C + 273 = 295 K
substituting the values in the equation

T = 492 K
new temperature - 492 - 273 = 219 °C