You are trying to determine the specific heat of a metal. You heat the 97 g piece of metal to 100 °C and place it in a calorimeter with 122 g of water. The temperature of the water increases from 20.0 °C to 28.9 °C. What is the specific heat of the metal?

Answer : The specific heat of the metal is,

Explanation :

In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

where,

= specific heat of metal = ?

= specific heat of water =

= mass of metal = 97 g

= mass of water  = 122 g

= final temperature of mixture =

= initial temperature of metal =

= initial temperature of water =

Now put all the given values in the above formula, we get

Therefore, the specific heat of the metal is,

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.

the answer is c.the valence of the atoms combine .