250gTi x (1mol/47.87 [molar mass]) =5.22247 moles
Answer:
Please see the attachments
Explanation:
Please see the attachments below structures of the 3 isomers of C8H18 that contain 3 methyl branches on the main chain, 2 of which are on the same carbon.
Answer:
Considering the half-life of 10,000 years, after 20,000 years we will have a fourth of the remaining amount.
Explanation:
The half-time is the time a radioisotope takes to decay and lose half of its mass. Therefore, we can make the following scheme to know the amount remaining after a period of time:
Time_________________ Amount
t=0_____________________x
t=10,000 years____________x/2
t=20,000 years___________x/4
During the first 10,000 years the radioisotope lost half of its mass. After 10,000 years more (which means 2 half-lives), the remaining amount also lost half of its mass. Therefore, after 20,000 years, the we will have a fourth of the initial amount.