Answer:
Here's what I've found
Explanation:
Refer to the attachment !
First write all of the compounds/atoms in either side then fill in existing values and balance
Na- 1
Br- 1
Ca- 1
Cl- 2
Na- 1
Cl- 1
Ca-1
Br-2
Balance to get
2NaBr+CaCl2=2NaCl+CaBr2
Use PV =nRT
so P = nRT/V
= 1 mole(0.08205 L atm/K mol)(1000K) / 2 L
= 41 atm