It will take 764 kJ of heat energy.
The energy #q# required to heat an object is given by the formula
#color(blue)(bar(ul(|color(white)(a/a)q = mcΔTcolor(white)(a/a)|)))" "#
where
#m# is the mass
#c# is the specific heat capacity
#ΔT# is the change in temperature
In your problem,
#m = "2.60 kg" = "2600 g"#
#c = "1.75 J·°C"^"-1""g"^"-1"#
#ΔT = T_"f" - T_"i" = "191 °C - 23 °C = 168 °C"#
∴ #q = 2600 color(red)(cancel(color(black)("g"))) × "1.75 J"·color(red)(cancel(color(black)("°C"^"-1"·"g"^"-1"))) × 168 color(red)(cancel(color(black)("°C"))) = "764 400 J" = "764 kJ"#
