Earth's atmosphere is 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide with very small percentages of other elements. Our atmosphere also contains water vapor. In addition, Earth's atmosphere contains traces of dust particles, pollen, plant grains and other solid particles.
Answer 16. True 17. True 18. False 19. True 20. False
The answer would be letter A.Among the alkali earth metals, the tendency to react with other substances <span>increases from bottom to top within the group. We know that when there is an increase of metallic property, there will also be an increase of reactivity. </span>
Radioactive decay or disintegration is a process through which unstable nuclei form q more stable nuclei by the release of elementary particles like alpha particles, beta, protons, neutrons etc along with the release of energy.
In the given examples:
a) N-13 will get converted in to carbon, C-12 along with the release of a proton as shown below:
₇N¹³ → ₆C¹² + ₁H¹
b) N-15 will get converted in to boron B-11 along with the release of an alpha particle
₇N¹⁵ → ₅B¹¹ + ₂He⁴
Answer:
b) Both p orbitals are perpendicular to the F−Be−F bond axes.
Explanation:
Be has 2 electrons in its valence shell, subshell s is fulfilled, so it has no unpaired electrons in its ground state to make bonds with F. So, it can promote the electrons to the 2p orbital and will having sp hybridization.
The bond between the orbitals sp and the p orbital of F are in opposite directions but the same ax. The two bonds are equivalent, and the molecule had a linear geometry. The two unhybridized p orbitals on Be are vacant, and so they are perpendicular to the F-Be-F bond axes.