Question 11 (4 points) What is the formula for the ionic compound formed by Mg2+ and N3−
Question 11 (4 points) What is the formula for the ionic compound formed by Mg2+ and N3−
Question 11 options:
Multiple Choice
1.Mg3N2
2.Mg3N3
3,Mg6N4
4.Mg2N2
Question 12 (8 points)
A certain radioactive substance has a half-life of 1 hour. If you start with a 1024 g sample at noon, how much is left at 10:00 PM?
Answer to one decimal place please in grams
Question 13 (10 points)
The average person in US uses around 1.0*10^8 J of energy per year. If the USA population is 308 million.
Using Einstein’s famous formula, E = m c^2, find the energy that would be released if a 65 kg of an radioactive element were converted entirely into energy. (Hint> First calculate E=mc^2. c=3*10^8 m/s.). Then calculate how many years that amount of energy will last the USA.
You answer is in years. Answer in integers.