Answer:carbon-14 levels in the atmosphere
Explanation:
When carrying out radiocarbon dating, the level of carbon-14 in a sample is compared with the level of carbon 14 in the atmosphere because, objects exchange carbon-14 with the atmosphere.
Comparison of the activities of carbon-14 in the atmosphere and in the sample gives the age of the sample since the half-life of carbon-14 is a constant.
Answer:
d) repeat
Explanation:
If the trend in a property is periodic, it means it will repeat on the periodic table.
Periodic properties on the table have a constant pattern as we move up or down a group or across a period from left to right.
- This helps to predict some of the salient properties of elements as we move through the periodic table.
- For example, on most periodic groups, metallicity increases as we move down the group and it decreases across the period.
Answer:
Sulfur
Explanation:
Sulfur is a chemical element that is represented with the chemical symbol "S" and the atomic number 16 on the periodic table.
Answer:
Decreases
Explanation:
The atmospheric pressure on the surface of the mercury pushes it up the evacuated tube until the downward pressure of the mercury equals the atmospheric pressure.
If the atmospheric pressure decreases, the mercury doesn't have to rise as high.
The mercury height decreases.
Answer:
B.
Explanation:
Most metals can be drawn into a wire while nonmetals would break apart.
