Strontium has 3 stable isotopes with mass numbers 86, 87 and 88. Their relative abundances are 9.97%, 7.0% and 82.6% respectively. How do the number of electrons and the electron configurations compare for atoms of the three isotopes

38 and [Kr] 5s2.

Explanation:

The number of electrons and the electronic configurations are the same for the three isotopes of Strontium because in isotopes number of neutron increases not number of proton or electron. Isotope of element having the same atomic number but with different atomic masses due to increase the number of neutrons in each isotope. So the number of electron in all isotopes are the same i.e. 38 and the electronic configuration is also the same i.e. [Kr] 5s2.

answer: the rate of diffusion increases with increase in temperature.

increase in temperature, increases the molecular/particles speed (kinetic energy. diffusion means movement of particles through the material.

generally, the heavier the particle the more it interacts with the environment and more the temperature matters. so higher temperature results in higher diffusion.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.