Let there be an object having some chemicals in it. It starts moving with a uniform velocity v, and a chemical reaction starts happening. In this case, which of the following statement/s is/are correct? 1) Chemical reactions happening in the system cannot change the velocity v of the centre of mass of the object. 2) Chemical reactions happening in the system cannot change the kinetic energy of the particles inside with respect to the centre of mass an object weighs 36g in air and has a volume of 8.0 cmof an object. Select the correct answer using the code given below:

Statement 1 is correct because chemical reactions involve internal forces between atoms and molecules . According to the law of conservation of momentum, in the absence of an external force, the velocity of the center of mass of a system remains constant. Since chemical reactions only involve the breaking and making of bonds within the system , they cannot change the translational momentum or the velocity of the center of mass. Statement 2 is incorrect because chemical reactions are either exothermic (releasing energy) or endothermic (absorbing energy) [2][3]. This energy exchange involves changes in the internal energy of the system, which includes the kinetic energy of the particles relative to the center of mass. For instance, in an exothermic reaction, chemical potential energy is converted into thermal kinetic energy [3], thereby changing the kinetic energy of the particles within the object's frame of reference.

Sources

1. [2] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > QUESTIONS > p. 7
2. [3] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > 1.2 TYPES OF CHEMICAL REACTIONS > p. 6