A substan e has a melting point of 20◦C and a heat of fusion of 3.5 × 104 J/kg. The boiling point is 150◦C and the heat of vaporization is 7.0 × 104 J/kg at a pressure of 1.0 atm. The spe i heats for the solid, liquid, and gaseous phases are 600 J/(kg. K), 1000 J/(kg. K), and 400 J/(kg. K), respe tively. The quantity of heat given up by 0.50 kg of the substan e when it is ooled from 170◦C to 88◦C, at a pressure of 1.0 atmosphere, is losest to

the answer is false. this is because for ice to melt, it requires latent heat of melting. latent heat means heat energy required to change phase without any increase in temperatures. therefore, the ice will take energy from the environment to melt hence atmospheric temperatures will reduce.

1.   what is light?

light is an electromagnetic wave visible to the human eye. 

2. what is a reflection?

the rebounding of a light ray when it hits a mirror.

3. what is the incident ray?

contacts the surface of an object.

4. what is the reflected ray?

bounces off a reflective surface.

5. what is the normal ray?

perpendicular to the surface of a mirror.

6. what is the angle of incidence?

an angle formed by the incident ray and the normal.

7. what is the angle of reflection?

an angle formed by the reflected ray and the normal.

8. what is refraction?

(bending.)

9. what is a converging lens?

bring together light rays that pass through.

10. what is a diverging lens?

spreads out light passing through.

11. focal point?

the real point where the refracted rays meet when the incident rays run parallel.

i copy pasted btw from an website..