If a person were to drink 2L of water a day containing 100ppb Nickel for an entire lifetime (assume 72yrs)
I took 100/1x10^-9 x 52596L=5.2596x10^-3? is this right?
or should it be 5.2596x10^15?
What's the question?
oh sorry :( how many grams of Ni would a person ingest in their lifetime? If a person drank 2L of water a day containing 100ppb Ni
I see this question all over the Internet. Which of your answers is correct? I don't think either of them. I saw the exact post on MY TUTOR and that answer is wrong, also, I think. The mistake there is that volume in liters was converted directly to grams but it should be converted to #L x 1000 = grams. That makes the answer 5.2 and not 0.0052 (and the density SHOULD have been taken into account).
The easy way to do these things is to remember that 1 ppb = 1 ug/L.
2L/day x (7 days/week) x (52 weeks/year) x 72 years = 52416 L in 72 years.
52416 L x (100 ug/L) = 5.2E6 ug which = 5.2 grams.
You get a slightly different answer if you use 365.25 days/year x 72 years but not wildly different.
To calculate the total amount of Nickel consumed over a lifetime, we can follow these steps:
1. First, we need to find the amount of Nickel consumed per day. We can do this by multiplying the concentration of Nickel (100 ppb) by the volume of water consumed per day (2L).
Nickel consumed per day = 100 ppb x 2L = 200 ppb·L.
2. Next, we need to convert the daily consumption to the total amount of Nickel consumed over a lifetime. Since you assumed a lifetime of 72 years, we need to multiply the daily consumption by the number of days in 72 years.
Total Nickel consumed = Nickel consumed per day x Number of days in 72 years.
To calculate the number of days in 72 years, we need to consider leap years. On average, a year has 365.25 days (accounting for leap years which have 366 days). Therefore:
Number of days in 72 years = 72 years x 365.25 days per year = 26,296 days.
Now we can calculate the total amount of Nickel consumed:
Total Nickel consumed = 200 ppb·L x 26,296 days = 5,259,200 ppb·L.
3. Finally, you converted the result to a more convenient scientific notation. 5,259,200 ppb·L can be written as scientific notation as follows: 5.2592 x 10^6 ppb·L.
Based on the calculations, it appears that your calculation is slightly off. The correct result should be 5.2592 x 10^6 ppb·L instead of 5.2596 x 10^-3 ppb·L.