The set that represent a pair of isotope is 9B AND 11B.
Isotopes are chemical element which have two or more forms, these forms have the same number of electrons but different number of neutrons.
In an atom of an element, the nucleus contains the neutron and the proton. For a neutral atom, the number of proton and neutron are always the same, while the number of neutron differ. Thus, for the correct option, B stands for the element Boron, which has atomic number of 5. This means that 9B has 5 electrons, 5 protons and 4 neutrons. For 11B, the isotope has 5 protons, 5 electrons and 6 neutrons. 9 and 11 are the mass number of the isotopes; mass number is the summation of number of proton and neutron.
The half life of a certain substance is being used to date fossils or to know their age. Most likely, it is carbon-14 that is the substance that is being traced in fossils since it is what remains after million of years in a fossil. The half life is important in determining the constant in the decay and, consequently, determining the age of the fossil.
Answer:
higher temperature → more kinetic energy → more space between particles higher volume
Explanation:
Kinetic Molecular Theory states that gas particles exhibit perfectly elastic collisions and remain in constant motion. Absolute temperature is directly proportional to the average kinetic energy of gas particles.
The following sequence represents the relationship between temperature and volume as explained by the kinetic-molecular theory:
higher temperature → more kinetic energy → more space between particles higher volume