Answer:
94.325 g
Explanation:
We'll begin by converting 350 mL to L. This can be obtained as follow:
1000 mL = 1 L
Therefore,
350 mL = 350 mL × 1 L /1000 mL
350 mL = 0.35 L
Next, we shall determine the number of mole of KC₂H₃O₂ in the solution. This can be obtained as follow:
Volume = 0.35 L
Molarity of KC₂H₃O₂ = 2.75 M
Mole of KC₂H₃O₂ =?
Molarity = mole /Volume
2.75 = Mole of KC₂H₃O₂ / 0.35
Cross multiply
Mole of KC₂H₃O₂ = 2.75 × 0.35
Mole of KC₂H₃O₂ = 0.9625 mole
Finally, we shall determine the mass of KC₂H₃O₂ needed to prepare the solution. This can be obtained as illustrated below:
Mole of KC₂H₃O₂ = 0.9625 mole
Molar mass of KC₂H₃O₂ = 39 + (12×2) +(3×1) + (16×2)
= 39 + 24 + 3 + 32
= 98 g/mol
Mass of KC₂H₃O₂ =?
Mass = mole × molar mass
Mass of KC₂H₃O₂ = 0.9625 × 98
Mass of KC₂H₃O₂ = 94.325 g
Thus, the mass of KC₂H₃O₂ needed to prepare the solution is 94.325 g
This is heated until evaporation occurs and sugar crystals are precipitated. This is similar to how chemical sedimentary rocks are formed (like rock salt or cave limestone). It is then separated into small individual crystals. This can be representative of weathering and erosion of rock into sediment
Answer:
2.86g
Explanation:
Mass of HCl = 2.87g
Mass of water = 3.75g
Mass of NaCl = 1.98g
Unknown:
Mass of NaOH reacted = ?
Solution:
The reaction expression is given as:
HCl + NaOH → NaCl + H₂O
According to the law of conservation of mass, the mass of reactants and products must be the same.
Mass of HCl + Mass of NaOH = Mass of NaCl + Mass of H₂O
2.87g + Mass of NaOH = 1.98g + 3.75g
Mass of NaOH = 1.98g + 3.75g - 2.87g = 2.86g
Answer and
Explanation
I believe the correct answer would be the last option. When an electrons moves from an excited state to the ground state, it would release energy. An electron in the excited state would mean that it contains high kinetic energy so to move to a lower state some of these energy should be released.