Answer: Hydrogen molecules will have greatest average speed.
Explanation:
The formula for average speed is :

R = gas constant
T = temperature
M = Molecular Mass
Now putting all the values:



Thus average speed of hydrogen is 8 times the average speed of oxygen. Thus hydrogen molecules will have greatest average speed
Answer:
<u>The temperature difference is</u> 
Explanation:
The formula that is to used is :
Δ
Δ
<em>where ,</em>
- <em>Δ
is the heat supplied in calories = 300cal</em> - <em>
is the mass of water taken = m (assumed)</em> - <em>Δ
is the change in temperature</em> - <em>
is the specific heat of water =
</em>
ΔT :

"As the molecules in a sample move faster the temperature reading will be lower" is not true.
Answer:
The temperature of the cold water is lower than the warm one. So, when we put the hand in the warm from the cold water, our hand will absorb heat, causing the hand to feel hot. Thus, we can conclude that the more heat it absorbs, the more hotter it is. Whereas the more heat it releases, the colder it is.