Answer:
3rd or 4th answer is correct
<span>1. What is the molar mass of gold?
Molar mass is a unit that expresses the mass of a molecule per one mol. The molar mass can be obtained by adding the neutron with the proton of the atoms. Gold has atomic number 79 so the proton is 79. The number of the neutron is 118. Then the molar mass would be: 79 + 118 = </span>197 g/mol<span>
</span><span>2. Calculate the number of moles of gold (Au) in the sample. Show your work.
</span>In this question, you are given the mass of the gold and asked for how many moles the sample has. To find the number of moles you just need to divide the weight by the molar mass.
For 45.39 grams of gold, the number of moles would be:
45.39 / (197g/mol)= 0.23 moles
3. Calculate the number of atoms of gold (Au) in the sample. Show your work.Moles is unit of a number of molecules but 1 mol doesn't represent 1 molecule. The number of atoms can be obtained by multiplying the number of moles with Avogadro number. The calculation would be:
0.23 moles * (6.023 * 10^23 molecules/mol)= 1.387 * 10^23 molecules
Answer:
The average kinetic energy of the particles in the mug decreases. The average kinetic energy of the particles in the coffee increases. Thermal energy from the mug is transferred to the coffee. Thermal energy from the coffee is transferred to the mug.
False, atoms can not be created that way
Answer:
The new volume of the balloon is 38.5 L
Explanation:
Step 1: Data given
Volume at the start = V1 = 35.0 L
Temperature at the start = T1 = 303 Kelvin
Volume by 3pm = TO BE DETERMINED
Temperature by 3pm = 333 Kelvin
<u>Step 2: </u>Calculate the new volume
Charles' gas law says
V1/T1 = V2/T2
V
1 is the initial volume and T1 is the initial temperature
V2 is the final volume and T2 is the final temperature
35 L / 303 Kelvin = V2 / 333 Kelvin
V2 = 35L * 333 Kelvin / 303 Kelvin
V2 = 38.47L ≈ 38.5 L
The new volume of the balloon is 38.5 L