Answer:

Explanation:
<u>1. Convert Atoms to Moles</u>
We must use Avogadro's Number: 6.022*10²³. This is the number of particles (atoms, molecules, ions, etc.) in 1 mole of a substance. In this case, the particles are atoms of helium. We can create a ratio.

Multiply by the given number of helium atoms.

Flip the fraction so the atoms of helium cancel.



<u>2. Convert Moles to Grams</u>
We must use the molar mass, which is found on the Periodic Table.
Use this as a ratio.

Multiply by the number of moles we calculated. The moles will then cancel.



<u>3. Round </u>
The original measurement has 3 significant figures (5, 5, and 0). Our answer must have the same. For the number we calculated, it is thousandth place. The 3 in the ten thousandth place tells us to leave the 5.

The mass is <u>0.365 grams of helium</u> so choice A is correct.
Answer:250 and your matthew sister
Jet Takeoff because it is the loudest according to the chart by the number of decibels.
Answer:
of water at 30C and 1 atm is 256.834 J/mol·K.
Explanation:
To solve the question, we note the Maxwell relation such as

Where:
= Specific heat of gas at constant pressure = 75.3 J/mol·K
= Specific heat of gas at constant volume = Required
T = Temperature = 30 °C = 303.15 K
α = Linear expansion coefficient = 3.04 × 10⁻⁴ K⁻¹
K = Volume comprehensibility = 4.52 × 10⁻⁵ atm⁻¹
Therefore,
75.3 -
= 
=
- 75.3 = 256.834 J/mol·K.