Answer: Thus 663 J of heat is released when 27.6 g
cools from 83.1 °C to 55.6 °C
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

Q = Heat released = ?
m = mass of substance = 27.6 g
C = specific heat capacity = 
Initial temperature=
= 
Final temperature =
= 
Change in temperature ,
Putting in the values, we get:

As the value of q is negative, it means the heat has been released and it is 663J
The difference between ordinary, analar and industrial reagents is the in the purity. Ordinary reagents are those whose purity meets the standard. Analar reagents are used in chemical analysis and they are of high purity but with known contaminants which again illustrates their use in chemical analyses.Finally the industrial reagents are not pure enough and they are used for industrial purposes as well for commercial use.
It is physical change because ? has changed alone not with chemicals
Answer:
700,000 holes
Explanation:
When heat energy occurs to produce free electrons, the number of free electrons produced is directly proportional and equal to the number of holes it produces at that time.
Hence, if silicon crystal (pure) has 700,000 free electrons, then the number of holes it have is also 700,000.
Answer: v=d−at
Explanation: I don't know if this will help