A.
Explanation:
Pioneer plants are to plants species that appear first in virgin land – such an after a volcanic eruption. They are mainly lower plants such as lichen, fungi, and noses. These species can grow on rocks and break them down over time to form soil. This is due to the fact that the plants have very shallow roots that can even grow in the small crevices of rocks and can draw water from the atmosphere – moisture. This releases the nutrients in the rocks and makes them available to higher plants that have deeper roots. The ecology of the region will ultimately be succeeded by a climax community over time, mainly dominated by tree species.
Two or more compounds that have same molecular formula but differ in the arrangement of atoms in molecule and thus posses different properties are known as isomers.
The molecular formula of pentane is
substituting one hydrogen from pentane with bromine results in the formation of monobromo derivatives of pentane having molecular formula,
.
The structure of monobromo derivatives of pentane that is 1-bromopentane, 2-bromopentane, and 3-bromopentane and having molecular formula,
is shown in the image.
The other two arrangements of monobromo derivatives of pentane that is 2-bromo-2-methylbutane and 2-bromo-3-methylbutane is shown in the image.
There are different structures of monobromo derivatives of pentane having molecular formula,
which contain a 4-carbon chain are 1- bromo-2-methylbutane and 1-bromo-3-methylbutane shown in the image.
The first ionization energy is the energy that the atom lost its first electrons. The energy decrease and the atom is more reactive. So from highest to lowest is Li>Na>K>Rb.
Answer:
1
only 4 is the significant figure
we take tailing zeroes as significant figures only in case of decimals