The answer is Al.
If it is a main group element with 3 electrons in its Lewis dot structure, it must be in group 3A. If it is in the 3p orbital section, then it must be in period 3, since the p orbital is a valence orbital and the number that preceeds it is the principal quantum number. Therefore, your answer is the element in period 3 and group 3A, which is aluminum.
Answer : The correct answer is option C.
Explanation:
Astronomers have observed that light from the distant object in the universe is shifted towards the frequency of red color which indicates that those object are receding or moving away from the planet earth.This phenomena was termed as Red shift .Same thing goes for galaxies which are very far away from the planet earth.
Where as if galaxies were moving towards the the planet earth their light would have shifted toward the frequency of blue color termed as blue shift.
Hence, the correct answer is option C.
Answer:
3Fe(s)+2O2(g)---->Fe3O4
this way you will have 3irons on both sides and 4 oxygens.
I hope this helps
Answer:b
Explanation:
I honestly don’t know if this I right but that would be my guess
Answer:
About 0.1738 liters
Explanation:
Using the formula PV=nRT, where p represents pressure in atmospheres, v represents volume in liters, n represents the number of moles of ideal gas, R represents the ideal gas constant, and T represents the temperature in kelvin, you can solve this problem. But first, you need to convert to the proper units. 215ml=0.215L, 86.4kPa is about 0.8527 atmospheres, and 15C is 288K. Plugging this into the equation, you get:

Now that you know the number of moles of gas, you can plug back into the equation with STP conditions:

Hope this helps!