The energy change if 84.0 g of CaO react with excess water is 98KJ of heat is released.
calculation
heat = number of moles x delta H
delta H = - 65.2 Kj/mol
first find the number of moles of CaO reacted
moles = mass/molar mass
the molar mass of CaO = 40 + 16= 56 g/mol
mass = 84 g
moles therefore = 84 g/56 g/mol =1.5 moles
Heat is therefore = 1.5 moles x -65.2 = - 97.8 Kj = -98 Kj
since sign is negative the energy is released
The answer is 3.5 × 10^-3
Nitrogen fixation is the process that makes atmospheric nitrogen available to plants by mutualistic and free-living bacteria. The process is undertaken by the rhizobium bacteria that live in root roots of plants such as legumes. The mutualistic relationship is that the plant supplies the bacteria with a habitat in which to live, water, and nutrients, and the bacteria supply nitrogen for making plant proteins.
The volume of the water in cubic meter is determined as 3.2 x 10⁶ m³ .
<h3>Weight of one gallon of water</h3>
The weight of 1 gal of water is given as 3785 g
Mass of 8.48 x 10⁸ gal = 3785 x 8.48 x 10⁸ = 3.2 x 10¹² g
<h3>Volume of the water in cubic meters</h3>
Volume = mass/density
Volume = 3.2 x 10¹² g/1 gmL
Volume = 3.2 x 10¹² mL x 10⁻⁶ m³/mL = 3.2 x 10⁶ m³
Thus, the volume of the water in cubic meter is determined as 3.2 x 10⁶ m³ .
Learn more about volume here: brainly.com/question/1972490
#SPJ1
Answer:
The last option
Explanation:
The Bohr model was an attempt to explain atomic hydrogen's spectrum. This was done by establishing energy levels of separate electron orbits in the atom.Thos model was followed by the Schrödinger model.
