Answer:
Most spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. ... The spiral arms are sites of ongoing star formation and are brighter than the surrounding disc because of the young, hot OB stars that inhabit them.
Explanation:
Answer:
I believe the answer is Newton's Second Law
Explanation:
Newton's Second Law states that the acceleration of an object will count on how much mass and the amount of force that is applied.
The bowling ball was dropped from the 10th story window and had more force than when the ball was dropped from the 5th story window because the 10th story window gave the bowling ball more acceleration.
Answer:
D
Explanation:
We know that the
reaction catalyzing power of a catalyst ∝ surface area exposed by it
Given
volume V1= 10 cm^3
⇒
hence r= 1.545 cm
also, surface area S1= 
now when the sphere is broken down into 8 smaller spheres
S2= 8×4πr'^2
now, equating V1 and V2 ( as the volume must remain same )

and solving we get
r'= r/2
therefore, S2=
S2=
S2= 2S1
hence the correct answer is
. The second run has twice the surface area.
Answer:
1116 g.
Explanation:
The balanced equation for the reaction is given below:
4Na + O₂ —> 2Na₂O
From the balanced equation above,
1 mole of O₂ reacted to produce 2 moles of Na₂O.
Next, we shall determine the theoretical yield of Na₂O. This can be obtained as follow:
From the balanced equation above,
1 mole of O₂ reacted to produce 2 moles of Na₂O.
Therefore, 9 moles of O₂ will react to produce = 9 × 2 = 18 moles of Na₂O.
Finally, we shall determine the mass in 18 moles of Na₂O. This can be obtained as follow:
Mole of Na₂O = 18 moles
Molar mass of Na₂O = (23×2) + 16
= 46 + 16
= 62 g/mol
Mass of Na₂O =?
Mass = mole × molar mass
Mass of Na₂O = 18 × 62
Mass of Na₂O = 1116 g
Thus, the theoretical yield of Na₂O is 1116 g.
The equation is:4Al+3O2----2Al2O3