Answer:
D. A reaction or change in a substance that results in a different substance
Explanation:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.
Answer:
A. Passive Transport is migration of a molecule from one side of the cell membrane to the other, from an area of high electrochemical potential to a region of lower electrochemical potential.
B. Diffusion is an individual molecule of a material moving from a high-concentration location to a low-concentration area over a semipermeable barrier
C. Osmosis is the movement of molecules of water through a cell's partly permeable membrane from a liquid with a large concentration of water molecules to a solution with a lower concentration of water molecules.
D. Facilitated Diffusion are molecules that diffuse across the plasma membrane with assistance from membrane proteins, such as channels and carriers.
E. Active transport is the transport of molecules across a cell membrane against a concentration gradient from a low-concentration region to a high-concentration region.
F. Selectively permeable is when some chemicals or ions pass across the membrane, while others are blocked.
G. Cellular respiration are organisms mix oxygen with food molecules, directing the chemical energy in these substances into life-sustaining processes while eliminating carbon dioxide and water as waste material.
Explanation:
There a 9 planets in the solar system.
Answer:
the weakest acid is B) HIO
Explanation:
pKa = - log Ka
the higher the value of pKa, the lower the dissociation, therefore, an acid will be stronger the lower its pKa.
a) HC2H3O2; Ka = 1.8 E-5
⇒ pKa1 = - Log (1.8 E-5) = 4.745
b) HIO; Ka = 23 E-11
⇒ pKa2 = - Log ( 23 E-11 ) = 9.638
c) HBrO; Ka = 23 E-9
⇒ pKa3 = - Log ( 23 E-9 ) = 7.638
d) HClO; Ka = 2.9 E-8
⇒ pKa4 = - Log ( 2.9 E-8 ) = 7.537
e) HCO2H; Ka = 63 E-5
⇒ pKa5 = - Log ( 63 E-5 ) = 3.200
from the values pKa, we places the acids from the weakest to the least weak:
1) pKa2; HIO (weakest)
2) pKa3
3) pKa4
4) pKa1
5) pKa5
Explanation:
If there are two bond pairs and two lone pairs of electrons the molecular geometry is angular or bent (e.g. H2O). Five electron pairs give a starting point that is a trigonal bipyramidal structure.
