Answer:

General Formulas and Concepts:
<u>Chemistry - Gas Laws</u>
- STP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 K
- Charles' Law:

Explanation:
<u>Step 1: Define</u>
Initial Volume: 5.0 L H₂ gas
Initial Temp: 273 K
Final Temp: 985 K
Final Volume: ?
<u>Step 2: Solve for new volume</u>
- Substitute:

- Cross-multiply:

- Multiply:

- Isolate <em>x</em>:

- Rewrite:

<u>Step 3: Check</u>
<em>We are given 2 sig figs as the smallest. Follow sig fig rules and round.</em>
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Extensive properties, as volume and mass, depend on the amount of material. So, you can have a sample of gold and a sample of copper with the same volume as long as you have different amount of each one.
On the other hand, intensive properties do not depend on the amound of material but on the chemical constitution of the material. Density is an intensive property, so gold and copper have different densities. That is why you can use intensive properties to characterize different materials.
Answer: The pH will be 3.87
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)

According to stoichiometry,
1 mole of
gives 1 mole of
Thus
moles of
gives =
moles of
Putting in the values:
![pH=-\log[0.000134]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B0.000134%5D)

Thus the pH will be 3.87
Answer:
8239.2g
Explanation:
Given parameters:
Number of atoms in Br = 6.2 x 10²⁵atoms
Unknown:
Mass of Br = ?
Solution:
From mole concepts, we know that:
1 mole of a substance contains 6.02 x 10²³ atoms/mol
Molar mass of Br = 80g/mol
6.2 x 10²⁵atoms x
x 80 x
= 8239.2g
Hypothesis is a prediction made therefore it is a