Boiling water results in no chemical change. If water is just heated to its boiling temperature then there is a physical change.
Answer:
Over the past few decades, humans have released so many different chemicals into the air that they have changed the mix of gases in the atmosphere. ... In addition, the exhaust from cars, trucks, and buses releases nitrogen oxides and sulfur dioxide into the air.
Glaciers capture large amount of carbon dioxide from atmosphere. When concentration of carbon dioxide molecules in glaciers increase, then strength and fracture toughness of ice are decreased and <span>that make glaciers vulnerable to cracking and splitting into fragments.
</span>That is because hydrogen bonds between water molecules in glaciers is decreased under increasing concentrations of carbon dioxide who <span>competes with the water molecules connected in the ice crystal.</span>