The radon-222 sample has a half-life of 3.8 days, and we are asked how many times would the mass divide in half after 23 days. First we calculate the amount of times division occurs by taking the number of days and dividing that by the number of days for one half-life to occur: 23/3.8 = 6.05.
We have 198.6 grams of sample, and we are going to divide it in half 6 times to determine how much of it remains after 23 days:
198.6/2 = 99.3 grams
99.3/2 = 49.65 grams
49.65/2 = 24.83 grams
24.83/2 = 12.41 grams
12.41/2 = 6.21 grams
6.21/2 = 3.1 grams
Therefore, we are left with 3.1 grams of radon-222 after 23 days if one half-life equals to 3.8 days.
Answer:
Potassium was the first metal to be isolated by electrolysis. It was discovered by the English chemist Sir Humphry Davy by decomposing molten potassium hydroxide (KOH) with a voltaic battery.
Explanation:
One candela per steradian is termed a lumen, which is the measure of light intensity people are most familiar with One foot candle is equivalent to one lumen per square foot
Answer:
Answer choice B
Explanation:
Since you do not know the volume of the liquid in each beaker, the one in the smaller beaker could have more substance and therefore more thermal energy. If they had the same amount of substance, then the more voluminous one would radiate faster. However, since you do not know this, there is no way to tell. PM me if you have more questions. Hope this helps!
Answer: 3.72 M
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant = 
t = age of sample = 15.0 minutes
a = let initial amount of the reactant = 10.0 M
a - x = amount left after decay process = ?
The concentration of 
in a solution after 15.0 minutes have passed is 3.72 M
