Answer:
C. The half-life of C-14 is about 40,000 years.
Explanation:
The only false statement from the options is that the half-life of C-14 is 40,000yrs.
The half-life of an isotope is the time it takes for half of a radioactive material to decay to half of its original amount. C-14 has an half-life of 5730yrs. This implies that during every 5730yrs, C-14 will reduce to half of its initial amount.
- All living organisms contain both stable C-12 and the unstable isotope of C-14
- The lower the C-14 compared to the C-12 ratio in an organism, the older it is.
Atoms are made up of three subatomic particles called protons, neutrons, and electrons.
Protons and neutrons are located in the nucleus.
All protons have a positive charge.
All neutrons have no charge or are neutral.
Electrons orbit around the nucleus and have a negative charge.
Answer:
12:7
Explanation:
To Determine: To calculate the formula of the unknown binary compound of oxygen and nitrogen and to ratio in the next compound of the series using given data.Answer:The formula of the unknown compound .The ratio for atoms of oxygen to nitrogen inis .The mass ratio of oxygen to nitrogen in next member of the series of compounds is .Explanation:The mass ratio of toinis .The mass ratio of toin theunknown compound is .The atomic mass of the oxygen is .The atomic mass of the nitrogen is .The mass ratio of to in a molecule can be represented as: …… (1)Here,is the number of atoms of the oxygen in the molecule.is the mass of an atom of oxygen.is the number of atoms of the nitrogen in the molecule.is the mass of an atom of nitrogen.For unknown compound, substitutefor , for and for mass ratio in equation (1).The ratio of atoms of oxygen to nitrogen is , therefore, the expected formulas of the unknown compound is and . If the unknown compound is in a series with then the formula of the unknown compound and the formula for the next member of the series is .The ratio for atoms of oxygen to nitrogen inis .For , substitute 5 for , for , 2 for and for in equation (1).The mass ratio of oxygen to nitrogen in next member of the series of the compounds is .
