<span>Some of the plants that made up coal were various ferns, and trees that no longer exist, like the lepidodendron, which was a scaly trunk with no limbs. Calamites, which are similar to the horsetail plant seen today. Seed ferns and glossopterids, also now extinct, were a basis for coal composition.</span>
Answer:
Hydrogen Bond
Explanation:
Hydrogen bonds allow two molecules to link together temporarily. Water molecules are made up of two hydrogen atoms and one oxygen atom, held together by polar covalent bonds. The polarity of the water molecule is what gives water its unique properties.
Ozone is produced naturally in the stratosphere. But this "good" ozone is gradually being destroyed by man-made chemicals referred to as ozone-depleting substances (ODS), including chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), halons, methyl bromide, carbon tetrachloride, and methyl chloroform. These substances were formerly used and sometimes still are used in coolants, foaming agents, fire extinguishers, solvents, pesticides, and aerosol propellants. Once released into the air these ozone-depleting substances degrade very slowly. In fact, they can remain intact for years as they move through the troposphere until they reach the stratosphere. There they are broken down by the intensity of the sun's UV rays and release chlorine and bromine molecules, which destroy the "good" ozone. Scientists estimate that one chlorine atom can destroy 100,000 "good" ozone molecules.
Answer: Chlorine-36 (^36Cl) is an isotope of chlorine.
Explanation: Chlorine has two stable isotopes and one naturally occurring radioactive isotope, the cosmogenic isotope ^36Cl.
<span>Most people's urine is darker in the morning as the kidneys work hard during the night to remove impurities and the urine is more concentrated.</span>
