Answer : The time required for decay is, 84 days.
Explanation :
Half-life of chromium-51 = 28 days
First we have to calculate the rate constant, we use the formula :
Now we have to calculate the time required for decay.
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = time taken by sample = ?
a = let initial activity of the sample = 100
a - x = amount left after decay process = 12.5
Now put all the given values in above equation, we get
Therefore, the time required for decay is, 84 days.
Polar.
Polar bonds have unequal sharing electrons while nonpolar, the opposite, has equal sharing electrons. This is a tactic typically used to determine whether or not a compound or element itself is polar or nonpolar.
Hope this helps!
This is a tricky question. All that matters are ratios of percentages, not percentages themselves. So no one should directly compare 27.2 with 42.9. We must and shall compare the ratios (27.2 to 72.8) and (42.9 to 57.1).
Take them both down to 1 to and see what happens.
Working out the formulas knowing atomic masses is a bit beside the point; this is how people first DISCOVERED the idea of atomic mass.
A
Carbon Oxygen
27.2g 72.8g (100-27.2)
Moles 27.2/12 72.8/16
2.27 4.55
Ratio 1 2
Do the same with the other
Answer: Option (A) is the correct answer.
Explanation:
Force acting on a dam is as follows.
F = 
.......... (1)
Now, when we double the depth then it means H is increasing 2 times and then the above relation will be as follows.
F' = 
F' = 
........... (2)
Now, dividing equation (1) by equation (2) as follows.
= 
Cancelling the common terms we get the following.
= 
4F = F'
Thus, we can conclude that if doubled the depth of the dam the hydrostatic force will be 4F.
