1. Why is it possible to use the periodic table to predict that the first ionization energy of Mg is greater than the first ionization energy of K? Why is it not possible to use the periodic table to predict whether the first ionization energy of K or Sr is larger? [Predict = decide without looking at numerical values] 2. How does the Bohr theory of the atom explain the fact that the spectrum obtained from a glowing tube of hydrogen gas displays discrete lines and not a continuous rainbow of colors?

3. Why do we find CF4 as a stable molecule and not CF3 or CF5?

4. Is the C2ClF molecule polar or non-polar? Describe in detail how you arrived at your conclusion.

The real answer is keeping the world healthy so we won’t die

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They cool it down and aluminum cools easily

1. why does the same side of the moon always face earthc.the rotational period of the moon is equal to one revolution around earth2. which is greater the moons period of rotation or its period of revolution  b.the moons revolution period around earth3.what was the major accomplishment of the apollo missions  c.sending the first human into space4. which of these space missions involved the deployment of lunar roversa. voyager 15. which scientists are going to explore next on kepler-186fd. evidence of existence of life6.which mission is not going to explore the outside of the solar  systemb.safir7.which technology limit the future of space explorationb. scientist must first develop certain technologies before missions can be completed.