Answer: 3.75 M
Explanation:
400 mL = 0.4 L
NaOH has a molar mass of around 40 g/mol.
= 1.5 moles
Molarity = 
= 3.75 M
Answer:
The mass number of an atom is equal to the number of protons plus the number of neutrons that it contains. In other words, the number of neutrons in an atom is its mass number minus its atomic number.
Explanation:
protons
The mass number of an atom is its total number of protons and neutrons. Atoms of different elements usually have different mass numbers , but they can be the same. For example, the mass number of argon atoms and calcium atoms can both be 40.
it is most likely a beaker, beacuse 300ml is quite a large volume. Otherwise, it would be a measuring cylinder or pippette
Answer:
3.72 mol Hg
General Formulas and Concepts:
<u>Chemistry - Atomic Structure</u>
- Reading a Periodic Table
- Using Dimensional Analysis
- Density = Mass over Volume
Explanation:
<u>Step 1: Define</u>
D = 13.6 g/mL
54.8 mL Hg
<u>Step 2: Identify Conversions</u>
Molar Mass of Hg - 200.59 g/mol
<u>Step 3: Find</u>
13.6 g/mL = x g / 54.8 mL
x = 745.28 g Hg
<u>Step 4: Convert</u>
<u />
= 3.71544 mol Hg
<u>Step 5: Check</u>
<em>We are given 3 sig figs. Follow sig fig rules and round.</em>
3.71544 mol Hg ≈ 3.72 mol Hg
Answer:
Mole fraction of solute is 0.0462
Explanation:
To solve this we use the colligative property of lowering vapor pressure.
First of all, we search for vapor pressure of pure water at 25°C = 23.8 Torr
Now, we convert the Torr to mmHg. Ratio is 1:1, so 23.8 Torr is 23.8 mmHg.
Formula for lowering vapor pressure is:
ΔP = P° . Xm
Where ΔP = P' (Vapor pressure of solution) - P° (Vapor pressure of pure solvent)
Xm = mole fraction
24.9 mmHg - 23.8 mmHg = 23mmHg . Xm
Xm = (24.9 mmHg - 23.8 mmHg) / 23mmHg
Xm = 0.0462
