Oxygen (o2) and nitrogen (n2) do not have much greenhouse effect, but several trace gases including carbon dioxide (co2), methane (ch4), nitrous oxide (n2o), and various chlorofluorocarbons are important greenhouse gases. the primary mechanism by which these greenhouse gases warm the earth is: a. preventing convection currents that take heat aloft, in the same way that the glass of a greenhouse stops convection currents and so makes the air in the greenhouse warmer. b.raising the atmospheric pressure, because squeezing air warms it, as we saw at the redwoods. c.experiencing chemical reactions with each other, which release energy. d.absorbing some of the infrared radiation emitted from the earth. e.making politicians mad, so they give speeches that heat the air.

A.Preventing convection currents that take heat aloft, in the same way that the glass of a greenhouse stops convection currents and so makes the air in the greenhouse warmer.

Explanation: when ultraviolet solar radiation penetrates into the Earth's atomosphere and heats it,

the conventional radiation is supposed to be radiated back into the atmosphere as heat.however this is prevented from happening due to green house gases,they absorb the radiant heat and retain this heat within the Earth's environment and so behaves like the glass barrier in green houses.these green house gases trap heat within the Earth causing global warming .

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.