Answer:
Therefore it will take 7.66 hours for 80% of the lead decay.
Explanation:
The differential equation for decay is


Integrating both sides
ln A= kt+c₁

[
]
The initial condition is A(0)= A₀,


.........(1)
Given that the
has half life of 3.3 hours.
For half life
putting this in equation (1)

[taking ln both sides,
]

⇒k= - 0.21
Now A₀= 1 gram, 80%=0.8
and A= (1-0.8)A₀ = (0.2×1) gram = 0.2 gram
Now putting the value of k,A and A₀in the equation (1)




⇒ t≈7.66
Therefore it will take 7.66 hours for 80% of the lead decay.
694,563,239 rounded to the nearest thousand is 694,563.
It's because the first digit from the right is for ones, second for tens, third for hundreds and fourth for thousands and that's the one that we should take a closer look at. You can round it either to 3 or 4, depends on the digit of hundreds. In this case 3239 is clearly closer to 3000 than 4000, that's why we round it to 694,563, not 694,564.
Refraction is the bending of light (it also happens with sound, water and other waves) as it passes from one transparent substance into another. This bending by refraction makes it possible for us to have lenses, magnifying glasses, prisms and rainbows. Even our eyes depend upon this bending of light. Hope this helps!
Answer:
Option (2)
Explanation:
Cohesion is usually defined as the contrasting property by which the water molecules are attached to one another, and adhesion is the property by which the molecular substances are linked to the molecules of other substances.
Since, the water molecules are able to form inter-molecular hydrogen bonding, so they are comprised of strong cohesive force.
And, as the water molecules are able to stick to the walls of the container, so they tend to show more of the properties for adhesion.
Thus, according to the given condition, water molecules are sticking to other substances and this is the property of adhesion.
Hence, the correct answer is option (2).
Osmosis is the passage of water molecules through a semi-permeable membrane from a solution of ___lower_____ concentration to ___higher_____ concentration.