Heat required to increase 1° Celsius temperature of one kilogram water is 

Heat is a form of energy. Heat energy can be transferred to other forms of energies. Heat flows from a hotter body to a colder body.

Units of heat:

• Calorie: It is the quantity of heat required to raise the temperature of 1 gram of water through 1°C
• Joule: It is the SI unit of Heat energy

1 Calorie = 4.186 joule

Here the heat required of 1 kg of water is being asked which will be equal to = 1000 × heat required of 1 kg of water = 1000 calorie

Hence the heat required to increase 1° Celsius temperature of one-kilogram water is 1000 calorie.