Answer: add up to eight
Explanation: NaO as one bond as it takes only one and seven to make eight. Leaving NaO with three lone pairs
Answer:
he predicted the properties from known elements above and belws the unknown in the same group
Explanation:
What allowed Mendeleev to make predictions of undiscovered elements
He realized that an element on this table with one known element above it and one known element below it had to have properties between the two known elements
How did Mendeleev predict gallium and germanium?
Based on gaps in the periodic table Mendeleev deduced that in these gaps belonged elements yet to be discovered. Based on other elements below and above in the same group he predicted the existence of eka-aluminum, eka-boron, and eka-silicon, later to be named gallium (Ga), scandium (Sc), and germanium (Ge).
We are given with the following pairs:
<span>carbon and oxygen
hydrogen and helium
gold and silver
and we are asked if there is a pair that will produce the same spectrum. The answer is
</span>No two elements produce the same spectrum.This is because a light spectrum is unique to each element.
Answer:
Three primary reasons. First, there is simply more water-covered places than dry ground places for the animals and plants to have lived. Second, the seas are much more crowded with the kinds of life that leave fossils than the land is. Third, the process that form fossils work very well under water.
Explanation: