Give two reasons why a gold ring is not made of 100% gold.
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It is also extremely expensive to process gold to its purest form, so pure gold jewelry would be ridiculously expensive, to the point of no demand.
Hope that helped =)
2. Pure gold isn't durable, and wouldn't last, nor would you be able to keep it on your finger since it's so soft. If you're gonna wear a ring for a life-time, it has to have durability.
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Help on identifying the solute and solvent
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To change 1.34 kg of ice at 0°C to water, you would need to add approximately 448 kJ of heat.
To calculate the amount of heat needed to convert ice at 0°C to water, we use the formula Q = m * Lf. Where Q is the Heat Transfer, m is the mass of the substance (ice in this case), and Lf is the heat of fusion for ice, which is 334 kJ/kg.
Plugging in the values we have: Q = 1.34 kg * 334 kJ/kg = 447.56 kJ.
Therefore, you would need to add approximately 448 kJ of heat to convert 1.34 kg of ice at 0°C to water at the same temperature.
Learn more about Heat Transfer here:
#SPJ11
The heat required to convert 1.34 kg of ice at 0°C to water at 0°C is approximately 450.24 kJ.
When the substance freezes (changes from liquid to solid), the same amount of energy is released back into the surroundings. When a substance changes its phase (solid to liquid or liquid to gas) at a constant temperature, the heat required for this process is known as the heat of fusion.
For ice at its meltingpoint (0°C), the heat of fusion is approximately 336 kJ/kg. Thus for 1.34 kg of ice, we can calculate the heat required by using the formula below:
Heat = mass × heat of fusion
Heat = 1.34 kg × 336 kJ/kg
Heat = 450.24 kJ.
Learn more about mass here:
The complete question is -
How much heat (in kJ) must be added to 1.34 kg of ice at 0°C to convert it to water at 0°C
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Considering the definition of molar mass and molarity, the volume of each compound is:
- NaCl= 0.1355 L
- C₂H₆O = 0.0622 L
- CH₃COOH = 0.047 L
Definition of molar mass
The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.
Definition of molarity
Molar concentration or molarity is a measure of the concentration of a solute in a solution and indicates the number of moles of solute that are dissolved in a given volume.
The molarity of a solution is calculated by dividing the moles of solute by the volume of the solution:
Molarity is expressed in units.
Volume required
You know that the molar mass of each compound is:
- NaCl = 58.44 g/mol
- C₂H₆O = 46.06 g/mol
- CH₃COOH = 60.0 g/mol
On the other side, you know that the mass of each compound is:
- NaCl = 2.14 g
- C₂H₆O = 4.30 g
- CH₃COOH = 0.85 g
Then, considering the definition of molar mass, the amount of moles of each compound is:
- NaCl =
= 0.0366 moles
- C₂H₆O =
= 0.0933 moles
- CH₃COOH =
= 0.0141 moles
The molarity of each compound is:
- NaCl = 0.27 M
- C₂H₆O = 1.50 M
- CH₃COOH = 0.30 M
Considering the molarity, the volume of each compound is calculated as:
- NaCl =
= 0.1355 L
- C₂H₆O =
= 0.0622 L
- CH₃COOH =
= 0.047 L
Learn more about
molar mass:
molarity:
number of moles : 2.14 / 58.44 = 0.0366 moles
V = n / M => 0.0366 / 0.270 = 0.1355 L
__________________________________________
b) C2H6O = 46.06 g/mol
number of moles : 4.30 / 46.06 = 0.0933 moles
V = n / M => 0.0933 / 1.50 = 0.0622 L
___________________________________________
c) CH3COOH = 60.0 g/mol
number of moles : 0.85 / 60.0= 0.0141 moles
V = n / M => 0.0141 / 0.30 = 0.047 L
___________________________________________
hope this helps!
True or False
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I hope this helps. Let me know in the comments if anything is unclear.
b. alpha
c. proton
d. positron
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b. will be easily separated.
c. lose their own properties.