All oxygen atoms have eight protons, and most have eight neutrons as well. what is the mass number of an oxygen isotope that has nine neutrons? what is the name of this isotope?

The mass number of an oxygen isotope that has nine neutrons is 17 and isotope is called as Oxygen-17.

Explanation:

Atomic number is defined as the number of protons or number of electrons that are present in an atom.

For a neutral atom:

Atomic number = Number of electrons = Number of proton

Atomic number= Number of protons = 8

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

Given: Number of neutrons = 9

Thus mass number = Number of protons + Number of neutrons = 8 + 9 = 17.

Isotopes are elements which have same atomic number but different mass number.

Thus the mass number of an oxygen isotope that has nine neutrons is 17 and isotope is called as Oxygen-17.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

the increase of protons   hope this