Electrons absorb energy, as they absorb energy they go from ground state to excited state and to return to ground state electrons release energy in the form of photons producing that color.
Answer:
its stored in the covalent bonds
Physical change
iron nail have high melting point, thus, when it is heated, it will not melt very easily.
chemical change
iron nail can rust due to the exposure to the air(oxygen). iron in the nail and oxygen in the air will react together to form iron oxide(rust).
furthermore, the reaction is irreversible.
A group of environmentalists were discussing the benefits and drawbacks associated with using fossil fuels. Which argument <span>best </span>fits the conversation?
Fossil fuels are cheaper than alternative forms of energy.Fossil fuel reserves will never be depleted.<span>Fossil fuels are easily renewed. </span><span>Fossil fuel use does not affect the environment.</span>
Answer:
353kg
Explanation:
2000 x 0.1765 = 353kg
for every 1 cubic metre of helium there is 0.1765 kg of it
the balloon is holding 2,000 cubic metres of the helium.
That means that there are 2000 times of 0.1765kg of helium in the balloon
so you times 0.1765kg by 2000
