every action of has an opposite and equal reaction so we know that the rifle moved back toward her shoulder because the bullet that was fired out of gun was moving at a very high speed.
At STP, or standard temperature and pressure, 1 mol of any gas will take up 22.4 liters of space. Assuming STP, 4.5 moles of H2 will take up 100.8L.
Answer:
a.option is the correct answer
Answer:
Gallium-72
Explanation:
The elements are identified by the number of protons of the atom, which is its atomic number.
In this case the number of protons 39 (atomic number 39) permit you to identify the element as gallium.
Now, to identify the isotope you tell the name of the element and add the mass number.
The mass number is the sum of the protons and the neutrons
In this case, the number of neutrons is the original 39 plus the 2 added suddenly, i.e. 39 + 2 = 41, so the mass number is 31 + 41 = 72
Therefore, the isotope is gallium - 72.
I believe it will be A. Density, temperature, and viscosity, can be found in water through tests. Hope this helps! Mark as brainly please!
