A physical change is a change to a sample of matter in which some properties of the material change, but the identity of the matter does not. Physical changes can further be classified as reversible or irreversible. The melted ice cube may be refrozen, so melting is a reversible physical change.
Answer:
I believe 11 is B 12 is C 13 is B and 14 is C
Answer:
666,480 Joules or 669.48 kJ
Explanation:
We are given;
- Volume of water as 2.0L or 2000 ml
but, density of water is 1 g/ml
- Therefore, mass of water is 2000 g
- Initial temperature as 20 °C
- Final temperature as 99.7° C
Required to determine the heat change
We know that ;
Heat change = Mass × Temperature change × specific heat
In this case;
Specific heat of water is 4.2 J/g°C
Temperature change is 79.7 °C
Therefore;
Heat change = 2000 g × 79.7 °C × 4.2 J/g°C
= 669,480 Joules 0r 669.48 kJ
Thus, the heat change involved is 666,480 Joules or 669.48 kJ
Answer: mechanical
Explanation:
its a big mechanicale thing