This is because butterfly caterpillars are host specific. Plant-wise, the caterpillars of some butterfly species like asters, black-eyed Susan, clover, lupines, milkweed, sedum or violets. Aspen, birch, cherry, hackberry, oak or willow trees make caterpillars of other butterfly species equally happy.
each Br-F bond would be polar or BF4-, there is an extra electron making this a polar molecule. PCl5 has the Cl atoms that must be as far apart from each other as possible and therefore would create equal but opposite pulls.ach Br-F bond would be polar or BF4-, there is an extra electron making this a polar molecule. PCl5 has the Cl atoms that must be as far apart from each other as possible and therefore would create equal but opposite pulls.
SiCl4 is covalent compound. Si--Cl bond is polar because Cl is more electronegativity than Si. Structure of SiCl4 molecule is tetrahedral. THis structure is symmetry which brings to the non-polar characteristic of SiCl4 molecule. This is because all the dipole moment in Si--Cl bond cancel out each other.The bond between Si--Cl is covalent bond. SiCl4 molecules hold together by intermolecular Van der Waals force of attraction.tructure of SiCl4 molecule is tetrahedral. THis structure is symmetry which brings to the non-polar characteristic of SiCl4 molecule. This is because all the dipole moment in Si--Cl bond cancel out each other.