Which substance combines with iron in the presence of water to form rust?(1 point) carbon dioxide

acid

oxygen

nitrogen

Which process is most likely responsible for the formation of limestone caves?(1 point)

hydrolysis

oxidation

carbonation

abrasion

Which option best describes hydrolysis?(1 point)

oxygen in water combining chemically with substances in rock

carbon dioxide reacting with water to form an acid that dissolves minerals in rock

hydrogen in water combining chemically with substances in rock

water reacting chemically with minerals in rock

Which type of region would be most likely to support chemical weathering?(1 point)

a polar region that is cold and dry all year long

a temperate region with warm summers and cold winters

a tropical region that is hot and humid all year long

a desert region with very little rain

1) Oxygen

2) Carbonation

3) Water reacting chemically with minerals in rock

4) A tropical region that is hot and humid all year long

Explanation:

1) Iron rust is formed when iron comes into contact water where there is oxygen present. The process of iron rusting occurs more quickly in the presence of ions from salt, due to the enabling electrochemical reactions

2) When carbonation of rain water occurs  by the mixing of rain water with atmospheric carbon dioxide, and the solution enters the soil, the weak acid formed dissolve the limestone with the capability to forms caves depending on the location conditions

3) Hydrolysis is a term used to describe a reaction wit water

4) Chemical weathering is the weakening of minerals and rocks by rain water chemicals which will be supported in the hot and humid weather condition that last all year long in the tropics.

according to the u.s. department of agriculture, the label of "certified organic" comes with a set of highly regulated standards for environmental stewardship and resource conservation. some of these include maintenance and improvement of soil quality, prevention of ground and surface water contamination, greenhouse gas regulation, encouragement of biodiversity and conservation of water and energy (see references 1). organic practices integrate natural methods such as mulching, plant diversity, native and adapted plants, crop rotation and the introduction of beneficial insects to control pests without synthetic pesticides.

environmental implications of pesticides

synthetic pesticides ensure high crop yields. while effective in achieving this goal, pesticides contaminate soil, air, ground and surface water, as well as the plants and animals that come into contact with these contaminated sources. freshwater and marine organisms are particularly susceptible to pesticides through agricultural runoff. pesticides also reduce soil fertility (necessitating the use of synthetic fertilizers) and can travel far from the original source, contaminating water and air hundreds of miles from the location of application (see references 2).

health implications of organics

although a subject of particular debate, many recent findings show that organic food is healthier than conventionally grown food. according to the usda, an extensive european union-funded study found that organically grown foods contain more beneficial compounds, such as the vitamins and antioxidants needed to combat many diseases (see references 5). organic milk, meat and eggs are regulated to ensure they are free of hormones administered to conventional livestock and poultry.

health implications of pesticides

pesticides affect human health in three ways: through skin contact, inhalation and ingestion. acute and long-term exposure to pesticides can cause serious health problems for farmers who apply them. the majority of other people are affected by drinking contaminated water and eating contaminated marine life (see references 3). pesticides have been linked to neurological disorders, endocrine and reproductive disorders, immune system deficiencies and cancer. according to the world health organization, acute pesticide poisoning (app) is responsible for significant annual mortality, especially in developing nations (see references 4).

other important considerations

not every small farm or business owner can afford the costly certification process required to be considered "certified organic," even if the farm is not using chemicals. "transitional" farms include those that once used chemicals and are now transitioning to organic-only production. in addition, though organic farming methods offer obvious environmental benefit, an organic apple shipped from around the world creates a different set of environmental problems. locally grown food (particularly locally grown, organic food) is key in sustainable food production.

i think it is true since you can test the answer and can use observations to complete it.