Number of neutrons.
The atomic number is a way of identifying elements so if the were all the same than that wouldn't work very well :)
Ethane consists of 6C−H bonds and 1C−C bond. Total number of bonds is 7. Each bond is made up of two electrons
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Answer:
The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Explanation:

Where:
Q = heat absorbed or heat lost
c = specific heat of substance
m = Mass of the substance
ΔT = change in temperature of the substance
We have mass of copper = m = 25.3 g
Specific heat of copper = c = 0.385 J/g°C
ΔT = 39°C - 22°C = 17°C
Heat absorbed by the copper :

The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Answer:
2.640
Explanation:
Rounding to the nearest whole number would be 3 if that is needed.
Answer: C (The first species to populate an uninhabited area)
Explanation: