<span>In a sample of solid Ba(NO3)2 the ratio of barium ions to nitrate ions is would be one is to 2 or 1:2. Barium ion has a formal charge of positive two which means that it needs two ions which has a formal charge of negative one or 1 ion with the formal charge of negative two. However, for this case, it is bonded to a nitrate ion which has a formal charge of negative one. Therefore, it needs two nitrate ions so that for every 1 atom of barium ion, we need two ions of nitrate ions.</span>
The direction of heat flow is from surroundings to system (air to ice), the dry ice is subliminating.
Answer:
Loss of biodiversity in the wetlands.
Explanation: Pollution can be defined as the emission of toxic, poisonous and harmful chemical substances which are capable of causing environmental degradation and contamination.
Nitrogen pollution enters Earth’s freshwater resources from a variety of human activities, including the use of fertilizers and pesticides in agriculture. This nitrogen pollution has a negative effect on plants and animals living in fresh water. Certain wetland plants, however, are able to purify the water and restore it to its non-polluted state.
Hence, what would most likely increase the negative effects of nitrogen pollution is a loss of biodiversity in the wetlands i.e the various species of animal and plants.
1) For example, sodium oxide (Na₂O).
One one molecule of sodium oxide has one sodium atome (Na) and two oxygen atoms (O).
The subscript after element shows the number of elements in a molecule.
2) Yes, it possible for two different compounds to be made from the exact same two elements.
This are isomers, same molecular formula, but different arrangements of atoms.
For example, n-butane (C₄H₁₀) and 2-methylpropane (C₄H₁₀).
3) There are large number of compounds in this world, around 40 millions.
<u>Answer:</u>

![\Delta E=-1312[\frac{1}{(n_f^2)}-\frac {1}{(n_i^2 )}]KJ mol^{-1}](https://tex.z-dn.net/?f=%5CDelta%20E%3D-1312%5B%5Cfrac%7B1%7D%7B%28n_f%5E2%29%7D-%5Cfrac%20%7B1%7D%7B%28n_i%5E2%20%29%7D%5DKJ%20mol%5E%7B-1%7D)
![\Delta E=-1312[\frac{1}{3^2)}-\frac {1}{(1^2 )}]KJ mol^{-1}](https://tex.z-dn.net/?f=%5CDelta%20E%3D-1312%5B%5Cfrac%7B1%7D%7B3%5E2%29%7D-%5Cfrac%20%7B1%7D%7B%281%5E2%20%29%7D%5DKJ%20mol%5E%7B-1%7D)
![\Delta E=-1312[\frac{1}{(9)}-\frac {1}{(1 )}]KJ mol^{-1}](https://tex.z-dn.net/?f=%5CDelta%20E%3D-1312%5B%5Cfrac%7B1%7D%7B%289%29%7D-%5Cfrac%20%7B1%7D%7B%281%20%29%7D%5DKJ%20mol%5E%7B-1%7D)
![\Delta E=-1312[0.111-1]KJ mol^{-1}](https://tex.z-dn.net/?f=%5CDelta%20E%3D-1312%5B0.111-1%5DKJ%20mol%5E%7B-1%7D)





h is planck's constant
c is the speed of light
λ is the wavelength of light

Wavelength

<em>Thus, the wavelength of light associated with the transition from n=1 to n=3 in the hydrogen atom is </em><u><em>103 nm.</em></u>