Answer: 2Liters
Explanation:
The expression used will be :
where,
= concentration of first antifreeze= 60%
= concentration of second antifreeze= 10%
= volume of first antifreeze = x L
= volume of second antifreeze = 8 L
= concentration of final antifreeze solution= 20%
= volume of final antifreeze = (x+8) L
Now put all the given values in the above law, we get the volume of antifreeze added
Therefore, the volume of 60% antifreeze solution that must be added is 2L
Answer:
Bohr's model
Explanation:
Rutherford's experimental evidence best supports the Bohr's model. Recall that in the Bohr's model, the Rutherford model was regarded as a fundamental stepping stone.
Experimental evidence from the Bohr's model shows that the atom is not a sphere of positive charges in which negative charges were embedded. It would have been impossible for Neils Bohr to build the quantum theory from such a model.
Hence, the nuclear theory of Rutherford provided a fundamental stepping stone and experimental backup for the Bohr's model of the atom.
All other models mentioned in task 1 (Dalton, Thompson and Bohr) all mention the fact that the atom is made of particles. Thompson effectively described the particles as negative and positive in nature. Bohr took the idea further by proposing that the negative particles (electrons) were actually found in energy levels that are quantized.
Answer:
D
Explanation:
Because the atomic number is 8, we can see that it is indeed an isotope of oxygen. If the mass number is 18, this means that the protons and neutrons added together = 18, so there are 10 neutrons. It does not have an atomic mass of 15.9994 like the element on the periodic table, however, as this is a confirmed isotope and not an average.
As you go down a group, the atoms get bigger. The bigger the atom, the more unstable it is. The more unstable it is, the more reactive the atom will be. So, as you go down a group, the nonmetals will become more reactive.
