The correct answer is:
D) a chemical change produces a new substance by breaking and forming new bonds
B. Most species that have lived on earth are now extinct. Ap3x
Answer:
Clouds are formed when water warms up and changes into a gas called water vapor, which rises up into the air.
Explanation:
Answer:
The coefficient for Al(s) is 2.
Explanation:
__ Al(s) __ O2(g) --> __ Al2O3(s)
__ Al(s) __ O2(g) --> 1 Al2O3(s)
1 Al(s) __ O2(g) --> 1 Al2O3(s)
1 Al(s) + 1.5 O2(g) --> 1 Al2O3(s) [Use a fraction to make it balance]
2 Al(s) + 3 O2(g) --> 2 Al2O3(s) [Convert the 1.5 fraction to a whole number by multiplying all coefficients by 2]
Answer:
In the n = 3 energy level
Explanation:
There's is no further explanation for this.
All the electrons in an energy level are distribuited according to the period in the periodic table they are.
So, if we have an atom in period 1, like Hydrogen (H), that atom would only have 1 level energy (n = 1) and in that level, we only have the sub level 1s.
Electrons in the 3d sublevel, are found mostly in all the transition metals of period 3, and it can go from 1 to 10 electrons. To be with the 3d sub level it's neccesary that the energy level to be 3.
energy levels beyond that, like n = 4, we have electrons occupying the 3d sub level, so, primordly, the 3d is found only in energy level 3.
Hope this helps