The balanced equation for the reaction is as follows;
Ca(OH)₂ + 2HBr --> CaBr₂ + 2H₂O
stoichiometry of Ca(OH)₂ to HBr is 1:2
number of Ca(OH)₂ moles reacted - 0.10 mol/L x 0.1000 L = 0.010 mol
Number of HBr moles added - 0.10 mol/L x 0.4000 = 0.040 mol
1 mol of Ca(OH)₂ needs 2 mol of HBr for neutralisation
therefore 0.010 mol of Ca(OH)₂ needs - 0.010 x 2 = 0.020 mol of HBr to be neutralised
but 0.040 mol of HBr has been added therefore number of moles of HBr in excess - 0.040 - 0.020 = 0.020 mol
then pH of the medium can be calculated using the excess H⁺ ions
HBr is a strong acid therefore complete ionization
[HBr] = [H⁺]
[H⁺] = 0.020 mol / (100.0 + 400.0 mL)
= 0.020 mol / 0.5 L
= 0.040 mol/L
pH = -log[H⁺]
pH = - log [0.040 M]
pH = 1.40
pH of the medium is 1.40
<span>B) The crystals did not phosphoresce within the drawer but did expose the film</span>
Most of the carbon is put away in sedimentary carbonates and kerogens, with the rest being spread between the sea, the air, biomass, for example, plants and creatures, and petroleum products
<u>Explanation</u>:
- The carbon cycle is the procedure where carbon goes from the surrounding into living beings and to the Earth and then again goes into the air. Plants take carbon dioxide from the air and use it for food preparation. Creatures at that point eat the nourishment and carbon is put away in their bodies or discharged as CO2 through the breath.
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Most of the carbon is put away in sedimentary carbonates and kerogens, with the rest being spread between the sea, the air, biomass, for example, plants and creatures, and petroleum products. This is known as carbon storage.
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For instance, carbon, a fundamental component in natural particles, is preserved as it is moved from inorganic carbon in a biological system to natural atoms in living life forms of the biological system and back as inorganic carbon to the earth.
Answer:
The electronic configuration of the magnesium atom shows that it has two unpaired outermost shell electrons while that of oxygen shows that it has six outermost shell electrons with two of them unpaired.
By means of elecron transfer, magnesium atom donates its two electrons to the oxygen atom to now have a charge of +2 while the oxygen then has a charge of -2. This results in an ionic bonding between the two atoms.
Explanation:
The structure is found in the attachment below