(08.05 MC) What is the hydronium ion concentration of a solution with a pOH of 6.90? (5 points) 6.53 x 10−7 M 6.29 x 10−7 M 7.94 x 10−8 M 7.18 x 10−8 M

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st drop outExplanation:

Step 1: convert the pOH to ph... 6.90 pOH is 7.1 ph.

Step 2: find out what we know, we know that the pH is 7.1

Step 3: What we need:

[ H3O+ ] = ?

[ OH− ] = ?

Step 4: Solve for hydronium ions:

[ H3O+ ] = 10−pH

[ H3O+ ] = 10^−7.1

[ H3O+ ] = 7.94328235 M

Step 5: Solve for hydroxide ions:

Using the ionization constant of water, we can use the concentration of hydronium ions to determine the concentration of hydroxide ions in the solution.

[ H3O+ ] = 10^−7.1

[ H3O+ ] = 7.94328235e-8 × 10^−13 M

[ OH− ] =

1.0 × 10−14 M/7.94 × 10−13 M

[ OH− ] = 1.25944584 × 10^-2 M

answer: option (4) is the correct answer.

explanation:

areas which are at low altitudes and near the equator tend to receive direct sunlight from the sun. hence, heat energy or radiations from the sun make these areas warmer and they have warmest water.

whereas areas which are at high altitudes and away from the equator do no receive direct sunlight. hence, no direct contact from the sun makes these regions colder and thus, they have colder water.

thus, we can conclude that the statement areas at low latitudes near the equator have the warmest water because they receive the most direct sunlight best explains the relationship between an area's geography and the temperature of its surface water.

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environmental implications of pesticides

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health implications of organics

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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.