<h3>
Answer:</h3>
1 grams Mercury-197
<h3>
Explanation:</h3>
From the question,
The radioisotope is Mercury-197
The half life of Mercury-197 is 3 days
Starting mass is 32 grams
Time taken is 15 days
We are required to calculate the final mass of the radioisotope after 15 days.
- Note that, half life is the time taken by radioisotope to decay by half its original amount.
- In this case, the half life of mercury-197 is 3 days, therefore, it takes three days for a mass of mercury-197 to decay by half its original mass.
Therefore, using the formula;
Final amount = Starting mass × (1/2)^n
where n is the number of half-lives (ratio of time to half life)
In our case, n = 15 days ÷ 3 days
= 5
Therefore;
Final mass = 32 g × (1/2)^5
= 32 g × 1/32
= 1 g
Therefore, the amount of mercury-197 in the shipment that will arrive is 1 g.
Answer:
+VE
Explanation:
If we look at the reaction profile pictured in the question, we can easily identify A as the enthalpy of the reaction. The enthalpy of reaction (ΔHrxn) is usually defined as the difference between the total enthalpy (heat content) of the products of a reaction and the total enthalpy (heat content) of the reactants in that reaction.
Looking at the figure, we can see that the enthalpy of products is greater than the enthalpy of reactants, hence ∆Hrxn is positive as stated in the answer above.
Answer: There are 4.8 x 1024 hydrogen atoms in 2.0 moles of CH4
