Answer:-
500324 grams
Explanation:-
Heat absorbed Q = M x Cp x T
We are given T = 10 [ The maximum allowed temperature increase]
Plugging in the values
6.70 x 10^ 6 J = M x 30.8 J / (K mol) x 10 K
M = 6.70 x 10 ^6 / (30.8 x 10)
= 21753 moles
Atomic Mass of sodium =23 gram / mol
Grams of liquid sodium required = 21753 moles x 23 grams / mol
= 500324 grams