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:
Ernest Rutherford
Explanation:
The Rutherford model, proposed originally in 1911, dipicts a planetary model of the atom in which there is a nucleus and electrons circling it.
To answer this question, you need to know the concept of half-life, which is how a radioactive material decreases in mass over time.
The half life of U-235 is 703.8 million years. The first part of this problem is to find the scale factor. To do this, divide the time that has past by the half life, like this:
Now, take this scale factor and multiply it by the current mass, like this:
This number is what you add to the current mass to get the original mass. That is because the scale factor showed us that it was just over one half life. Since after one half life, the mass is cut in half, and this is over one half life, when we add to the original it will be a little over double. This equation illustrates the final addition:
I hope this helped you. Fell free to ask any further questions.
You can solve this by using the equation (P1V1/T1) = (P2V2/T2). Plug in 0.50 atm for P1, leave V1 as the unknown, and plug in 325 K as T1. Then substitute 1.2 atm for P2, 48 L for V2, and 320 K for T2. Solve for V1, which is 117L, but since you round using two sig figs, your answer is C, 120 L. Hope this helps!
Each of the Nitrogen atoms has 2 non bonded valence electrons, meaning that there are 4 pairs total.
