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: PV = nRT
A gas at STP... This means that the temperature is 0°C and pressure is 1 atm.
R is the gas constant which is 0.08206 L*atm/(K*mol)
Rearranging for volume
V = nRT/P
The temperature and number of moles are held constant. This means that this uses Boyle's Law. (The ideal gas law could be manipulated to give us this result when T and n are held constant.)
PV = k
where k is a constant.
This means that
P₁V₁ = k = P₂V₂
P₁V₁ = P₂V₂
(1 atm) * (1 L) = (2 atm) * V₂
V₂ = 0.5 L
The new volume of the gas is 0.5 L.
Explanation:
Answer:
The pitch of the sound a person makes is determined by several factors, including the size and tension of his or her vocal cords.
Explanation:
The daughter isotope : Radon-222 (Rn-222).
<h3>Further explanation</h3>
Given
Radium (Ra-226) undergoes an alpha decay
Required
The daughter nuclide
Solution
Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,
- alpha α particles ₂He⁴
- beta β ₋₁e⁰ particles
- gamma particles ₀γ⁰
- positron particles ₁e⁰
- neutron ₀n¹
The decay reaction uses the principle: the sum of the atomic number and mass number before and after decay are the same
Radium (Ra-226) : ₈₈²²⁶Ra
Alpha particles : ₂⁴He
So Radon-226 emits alpha α particles ₂He⁴ , so the atomic number decreases by 2, mass number decreases by 4
The reaction :
₈₈²²⁶Ra ⇒ ₂⁴He + ₈₆²²²Rn
They dim unless more volts are added (batteries")