Answer: number of atoms is 5.21 · 10^24
Explanation: Atomic mass of Be is 9.012 g/mol.
Number of moles n = m/M = 78.0 g / 9.012 g/mol =
Multiply this with Avogadro number Na = 6.022*10^23 1/mol
Answer:
1. EXPOSE TWO GROUPS TO THE AROMA OF CHOCOLATE CHIP COOKIES BAKING
2.HAVE ONE GROUP EAT ONLY CHOCOLATE CHIPS COOKIES, AND HAVE THE OTHER GROUP EAT ONLY RADISHES
3.
There is an unstable ratio of protons and neutrons. Because protons are positively charged but neutrons have no charge, an increase in the number of protons means there needs to be an increase in the number of neutrons to "bind" the nucleus together. This is because like charges repel, so the protons will repel each other, and if there aren't enough neutrons to act as "glue" to hold the nucleus together, the nucleus will break apart.
The question is incomplete. The complete question is:
The half-life for the decay of carbon-14 is 5.73x10^3 years. Suppose the activity due to the radioactive decay of the carbon-14 in a tiny sample of an artifact made of woodfrom an archeological dig is measured to be 2.8x10^3 Bq. The activity in a similiar-sized sample of fresh wood is measured to be 3.0x10^3 Bq. Calculate the age of the artifact. Round your answer to 2 significant digits.
Answer:
570 years
Explanation:
The activity of the fresh sample is taken as the initial activity of the wood sample while the activity measured at a time t is the present activity of the wood artifact. The time taken for the wood to attain its current activity can be calculated from the formula shown in the image attached. The activity at a time t must always be less than the activity of a fresh wood sample. Detailed solution is found in the image attached.