Explanation:
Just a few things to remember:
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# of neutrons = Mass number - # protons
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Mass number = # protons + # neutrons
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Atomic Number = # of protons
- # of electrons = # of protons - charge on the atom
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Symbol - use the atomic number to find the element in the periodic table
Some electric appliances can be immersed in water without damage because they are well insulated. The electrical systems are well insulated and tightly sealed so that when they are immersed in water, no water can get into the electrical parts.
Answer is: the freezing point of the solution of sucrose is -0.435°C.
m(H₂O) = 100 g ÷ 1000 g/kg = 0.1 kg.
m(C₁₂H₂₂O₁₁) = 8.0 g.
n(C₁₂H₂₂O₁₁) = m(C₁₂H₂₂O₁₁) ÷ M(C₁₂H₂₂O₁₁).
n(C₁₂H₂₂O₁₁) = 8.0 g ÷ 342.3 g/mol.
n(C₁₂H₂₂O₁₁) = 0.0233 mol.
b(solution) = n(C₁₂H₂₂O₁₁) ÷ m(H₂O).
b(solution) = 0.0233 mol ÷ 0.1 kg.
b(solution) = 0.233 m.
ΔT = b(solution) · Kf(H₂O).
ΔT = 0.233 m · 1.86°C/m.
ΔT = 0.435°C.
Tb = 0°C - 0.435°C = -0.435°C.
Answer:
0.0063mol
Explanation:
Number of moles (n) in a substance can be calculated by dividing the number of atoms (nA) of that substance by Avagadro's number i.e. 6.02 × 10^23. That is; n = nA ÷ 6.02 × 10^23
1 mol of Gold = 6.02 × 10^23 atoms
Therefore, 3.8 x 10^21 atoms of Gold will be;
3.8 x 10^21 ÷ 6.02 × 10^23
= 3.8 ÷ 6.02 × 10^ (21 - 23)
= 0.6312 × 10^-2
= 0.0063mol of Gold
Answer: 1169.298 L
Explanation: In order to go from grams to liters, you must find the moles first using the molar mass, 62.068 g/mol (found via google search). I will assume the ethylene glycol is in gas form so we can use the 22.4 L per mol conversion.
Using dimensional analysis, starting with the kg, we must convert to grams, then moles, then liters.
Multiply the top individually, then the bottom individually.
Divide out.
In the end, we get 1169.298 L of ethylene glycol.