The rate of change in the amount of silver supplied is equal to the ratio of the difference in the amount supplied to the number of years elapsed from 2005 to 2008. That is,
rate of change = (25 - 200) / (2008 - 2005) = -173/3
The answer is letter A.
Answer:
A well tested explanation of a natural phenomenon
Explanation:
A scientific theory is an explanation of a natural phenomenon which has been drawn from a well tested observation.
Theories are products of repeated scientific experiments. When a hypothesis otherwise known as a "scientific guess" survives a lot of scrutiny, we can elevate it to the status of a theory. Most theories starts off from simple observations. These observations can further spark series of experiments in such a field and a scientific guess proposed. Further testing and experimenting would now lead to a theory.
It behaved as a catalyst (the acid hydrolysis )
Increase, because you need heat to melt a solid to a liquid, so the temperature will have to get greater.
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.
