From Earth's<span> density we can estimate what elements must compose the </span>Earth; an iron core<span> just happens to estimate </span>Earth's<span> mass the best. Now from energy waves, geologists use seismometers to measure movements in </span>Earth's<span> interior (e.g. Earthquakes), These energy-waves form compressional and shear waves</span>
Answer:
Groups 14, 15, and 16 have 2,3, and 4 electrons in the p sublevel (p sublevel has 3 "spaces" AKA orbitals), because Hunds says one in each orbital before doubling up if you had 2 electrons, group 14, they would both be in the first orbital, with 3 electrons, group 15, two in the first orbital one in the 2nd none in the 3rd. With 4 electrons, group 16, then you would have 2 in the first 2 orbitals and NONE in the 3rd.
Explanation:
If you are in group 13 you only have 1 electron so it can only be in one orbital. with group 17, you have 5 electrons, so 2 in the first 2 in the second and 1 in the 3rd, correct for Hunds rule anyway. Noble gasses, group 18, have 6 elecctrons, so every orbital is full any way you look at it.
Answer:
Explanation:
Volume of a cone:
We have 
and we want to find 
when the height is 2 cm.
We can see in our equation for the volume of a cone that we have three variables: V, r, and h.
Since we only have dV/dt and dh/dt, we can rewrite the equation in terms of h only.
We are given that the height of the cone is 1/5 the radius at any given time, 1/5r, so we can write this as r = 5h.
Plug this value for r into the volume formula:
Differentiate this equation with respect to time t.
Plug known values into the equation and solve for dh/dt.
Divide both sides by 100π to solve for dh/dt.
The height of the cone is increasing at a rate of 1/10π cm per second.
Answer:
d. 4 Al(s) + 3 O₂(g) → 2 Al₂O₃(s)
Explanation:
Aluminum metal reacts with oxygen gas in a combination reaction that forms a product that coats the metal preventing it from further oxidation: aluminum oxide. Aluminum is a cation with charge 3+ (Al³⁻) and oxide is an anion with charge 2- (O²⁻). Thus, the neutral compound aluminum oxide has the chemical formula Al₂O₃. The unbalanced chemical equation is:
Al(s) + O₂(g) → Al₂O₃(s)
We can balance using the trial and error method. First, we will balance O atoms by multiplying Al₂O₃ by 2 and O₂ by 3.
Al(s) + 3 O₂(g) → 2 Al₂O₃(s)
Finally, we get the balanced equation by multiplying Al by 4.
4 Al(s) + 3 O₂(g) → 2 Al₂O₃(s)
The controlled variable, I think.
