Answer:
C. Scientists accepted the model at first but later rejected it.
Explanation:
Scientists accepted the model at first because it explained the hydrogen emission spectrum.
However, with the development of quantum mechanics, scientists had to modify the model (not reject it).
Electrons still had specific energies, but they no longer travelled in fixed orbits.
Instead, electrons had a probability of being found in a given region of space.
The only answer we can choose
<span>B.
energy needed to break chemical bonds.</span>
due to there reactive rate?
Answer:
B - (C , Al, P, Cl)
Explanation:
How I got this answer was by looking at my periodic table it shows you how much it contains by the Atomic number.
Atomic number on C (Carbon) is- 6
Atomic number on Al (Aluminum) is - 13
Atomic number on P (Phosphorus) is - 15
Atomic number on Cl (Chlorine) is - 17
Now it says least to greatest and the other options are wrong I did the work for you hope this helps :)) I also had this project you didnt ask but the answer for the The Lesson are {B E M S} which as the code numbers are gonna be -7494- Im glad to help if you need more help I will give you the other answers as well :) !
Answer:
2Al+1.5O2→Al2O3
Thus, 2 mol of Al combine with 1.5 mol of oxygen to form 1 mol of Al2O3.
2 mol of Al corresponds to 2×27=54 g.
Thus, the weight of Al used in the reaction is 54 g.